Postcard printing camera

ABSTRACT

A recyclable, one-time use, print on demand, digital camera includes an image sensor device for sensing an image. A processor processes the sensed image. A pagewidth printhead prints the sensed image. An ink supply arrangement supplies ink to the print-head and the image is printed on print media from a supply of print media. The supply of print media is pre-marked with tokens designating that postage has been paid so that each image printed out on the print media has one such token associated with it.

CROSS REFERENCE TO RELATED APPLICATION

This is a Continuation application of Ser. No. 09/663,153, filed Sep.15, 2000, now Issued U.S. Pat. No. 6,738,096, which is a divisional ofand claims the benefit of U.S. application Ser. No. 09/113,086 filed onJul. 10, 1998, (now abandoned.)

FIELD OF THE INVENTION

The present invention relates substantially to the concept of adisposable camera having instant printing capabilities and inparticular, discloses a method integrating the electronic components ofa camera system.

BACKGROUND OF THE INVENTION

Recently, the concept of a “single use” disposable camera has become anincreasingly popular consumer item. Disposable camera systems presentlyon the market normally include an internal film roll and a simplifiedgearing mechanism for traversing the film roll across an imaging systemincluding a shutter and lensing system. The user, after utilizing asingle film roll returns the camera system to a film development centerfor processing. The film roll is taken out of the camera system andprocessed and the prints returned to the user. The camera system is thenable to be re-manufactured through the insertion of a new film roll intothe camera system, the replacement of any worn or wearable parts and there-packaging of the camera system in accordance with requirements. Inthis way, the concept of a single use “disposable” camera is provided tothe consumer.

Recently, a camera system has been proposed by the present applicantwhich provides for a handheld camera device having an internal printhead, image sensor and processing means such that images sense by theimage sensing means, are processed by the processing means and adaptedto be instantly printed out by the printing means on demand. Theproposed camera system further discloses a system of internal “printrolls” carrying print media such as film on to which images are to beprinted in addition to ink for supplying to the printing means for theprinting process. The print roll is further disclosed to be detachableand replaceable within the camera system.

Unfortunately, such a system is likely to only be constructed at asubstantial cost and it would be desirable to provide for a moreinexpensive form of instant camera system which maintains a substantialnumber of the quality aspects of the aforementioned arrangement.

It would be further advantageous to provide for the effectiveinterconnection of the sub components of a camera system.

SUMMARY OF THE INVENTION

According to the invention, there is provided a recyclable, one-timeuse, print on demand, digital camera comprising:

an image sensor device for sensing an image;

a processing means for processing said sensed image;

a pagewidth print head for printing said sensed image;

an ink supply means for supplying ink to the print head; and

a supply of print media on to which said image is printed, the supply ofprint media being pre-marked with tokens designating that postage hasbeen paid so that each image printed out on the print media has one suchtoken associated with it.

Preferably, the supply of print media is in the form of a roll, thetokens being pre-printed at regularly spaced intervals on one surface ofthe print media.

Each token may have an address zone and a blank zone for writingassociated with it on said one surface to provide a postcard effect.

Each image may be printed on an opposed surface of the print media.

The token may be in the form of a postage stamp which is in a currencyof a country in which the camera is bought, with a notice to that effectbeing carried on an exterior of that camera. Preferably, the camera hasa sleeve placed about a casing of the camera. The notice may then becarried on the sleeve of the camera.

BRIEF DESCRIPTION OF THE DRAWINGS

Notwithstanding any other forms which may fall within the scope of thepresent invention, preferred forms of the invention will now bedescribed, by way of example only, with reference to the accompanyingdrawings in which:

FIG. 1 illustrates a front perspective view of the assembled camera ofthe preferred embodiment;

FIG. 2 illustrates a rear perspective view, partly exploded, of thepreferred embodiment;

FIG. 3 is a perspective view of the chassis of the preferred embodiment;

FIG. 4 is a perspective view of the chassis illustrating mounting ofelectric motors;

FIG. 5 is an exploded perspective view of the ink supply mechanism ofthe preferred embodiment;

FIG. 6 is a rear perspective view of the assembled form of the inksupply mechanism of the preferred embodiment;

FIG. 7 is a front perspective view of the assembled form of the inksupply mechanism of the preferred embodiment;

FIG. 8 is an exploded perspective view of the platten unit of thepreferred embodiment;

FIG. 9 is a perspective view of the assembled form of the platten unit;

FIG. 10 is also a perspective view of the assembled form of the plattenunit;

FIG. 11 is an exploded perspective view of the printhead recappingmechanism of the preferred embodiment;

FIG. 12 is a close up, exploded perspective view of the recappingmechanism of the preferred embodiment;

FIG. 13 is an exploded perspective view of the ink supply cartridge ofthe preferred embodiment;

FIG. 14 is a close up, perspective view, partly in section, of theinternal portions of the ink supply cartridge in an assembled form;

FIG. 15 is a schematic block diagram of one form of chip layer of theimage capture and processing chip of the preferred embodiment;

FIG. 16 is an exploded perspective view illustrating the assemblyprocess of the preferred embodiment;

FIG. 17 illustrates a front exploded perspective view of the assemblyprocess of the preferred embodiment;

FIG. 18 illustrates a perspective view of the assembly process of thepreferred embodiment;

FIG. 19 illustrates a perspective view of the assembly process of thepreferred embodiment;

FIG. 20 is a perspective view illustrating the insertion of the plattenunit in the preferred embodiment;

FIG. 21 illustrates the interconnection of the electrical components ofthe preferred embodiment;

FIG. 22 illustrates the process of assembling the preferred embodiment;and

FIG. 23 is a perspective view further illustrating the assembly processof the preferred embodiment.

DESCRIPTION OF PREFERRED AND OTHER EMBODIMENTS

Turning initially simultaneously to FIG. 1 and FIG. 2 there areillustrated perspective views of an assembled camera constructed inaccordance with the preferred embodiment with FIG. 1 showing a frontperspective view and FIG. 2 showing a rear perspective view. The camera1 includes a paper or plastic film jacket 2 which can include simplifiedinstructions 3 for the operation of the camera system 1. The camerasystem 1 includes a first “take” button 4 which is depressed to capturean image. The captured image is output via output slot 6. A further copyof the image can be obtained through depressing a second “printer copy”button 7 whilst an LED light 5 is illuminated. The camera system alsoprovides the usual viewfinder 8 in addition to a CCD imagecapture/lensing system 9.

The camera system 1 provides for a standard number of output printsafter which the camera system 1 ceases to function. A prints leftindicator slot 10 is provided to indicate the number of remainingprints. A refund scheme at the point of purchase is assumed to beoperational for the return of used camera systems for recycling.

Turning now to FIG. 3, the assembly of the camera system is based aroundan internal chassis 12 which can be a plastic injection molded part. Apair of paper pinch rollers 28, 29 utilized for de-curling are snapfitted into corresponding frame holes eg. 26, 27.

As shown in FIG. 4, the chassis 12 includes a series of mutually opposedprongs e.g. 13, 14 into which is snapped fitted a series of electricmotors 16, 17. The electric motors 16, 17 can be entirely standard withthe motor 16 being of a stepper motor type. The motors 16, 17 includecogs 19, 20 for driving a series of gear wheels. A first set of gearwheels is provided for controlling a paper cutter mechanism and a secondset is provided for controlling print roll movement.

Turning next to FIGS. 5 to 7, there is illustrated an ink supplymechanism 40 utilized in the camera system. FIG. 5 illustrates a rearexploded perspective view, FIG. 6 illustrates a rear assembledperspective view and FIG. 7 illustrates a front assembled view. The inksupply mechanism 40 is based around an ink supply cartridge 42 whichcontains printer ink and a print head mechanism for printing outpictures on demand. The ink supply cartridge 42 includes a side aluminumstrip 43 which is provided as a shear strip to assist in cutting imagesfrom a paper roll.

A dial mechanism 44 is provided for indicating the number of “printsleft”. The dial mechanism 44 is snap fitted through a correspondingmating portion 46 so as to be freely rotatable.

As shown in FIG. 6, the mechanism 40 includes a flexible PCB strip 47which interconnects with the print head and provides for control of theprint head. The interconnection between the Flex PCB strip and an imagesensor and print head chip can be via Tape Automated Bonding (TAB)strips 51, 58. A molded aspherical lens and aperture shim 50 (FIG. 5) isalso provided for imaging an image onto the surface of the image sensorchip normally located within cavity 53 and a light box module or hood 52is provided for snap fitting over the cavity 53 so as to provide forproper light control. A series of decoupling capacitors e.g. 34 can alsobe provided. Further a plug 45 (FIG. 7) is provided for re-plugging inkholes after refilling. A series of guide prongs e.g. 55-57 are furtherprovided for guiding the flexible PCB strip 47.

The ink supply mechanism 40 interacts with a platten unit 60 whichguides print media under a printhead located in the ink supplymechanism. FIG. 8 shows an exploded view of the platten unit 60, whileFIGS. 9 and 10 show assembled views of the platten unit. The plattenunit 60 includes a first pinch roller 61 which is snap fitted to oneside of a platten base 62. Attached to a second side of the platten base62 is a cutting mechanism 63 which traverses the platen unit 60 by meansof a rod 64 having a screw thread which is rotated by means of coggedwheel 65 which is also fitted to the platten base 62. The screw threadedrod 64 mounts a block 67 which includes a cutting wheel 68 fastened viaa fastener 69. Also mounted to the block 67 is a counter actuator whichincludes a pawl. The pawl 71 acts to rotate the dial mechanism 44 ofFIG. 6 upon the return traversal of the cutting wheel. As shownpreviously in FIG. 6, the dial mechanism 44 includes a cogged surfacewhich interacts with pawl 71 thereby maintaining a count of the numberof photographs by means of numbers embossed on the surface of dialmechanism 44. The cutting mechanism 63 is inserted into the platten base62 by means of a snap fit via clips e.g. 74.

The platen unit 60 includes an internal recapping mechanism 80 forrecapping the printhead when not in use. The recapping mechanism 80includes a sponge portion 81 and is operated via a solenoid coil so asto provide for recapping of the print head. In the preferred embodiment,there is provided an inexpensive form of printhead re-capping mechanismprovided for incorporation into a handheld camera system so as toprovide for printhead re-capping of an inkjet printhead.

FIG. 11 illustrates an exploded view of the recapping mechanism whilstFIG. 12 illustrates a close up of the end portion thereof. There-capping mechanism 80 is structured around a solenoid including a 16turn coil 75 which can comprise insulated wire. The coil 75 is turnedaround a first stationery solenoid arm 76 which is mounted on a bottomsurface of the platen base 62 (FIG. 8) and includes a post portion 77 tomagnify effectiveness of operation. The arm 76 can comprise a ferrousmaterial.

A second moveable arm 78 of the solenoid actuator is also provided. Thearm 78 is moveable and is also made of ferrous material. Mounted on thearm is a sponge portion surrounded by an elastomer strip 79. Theelastomer strip 79 is of a generally arcuate cross-section and acts as aleaf spring against the surface of the printhead ink supply cartridge 42(FIG. 5) so as to provide for a seal against the surface of theprinthead ink supply cartridge 42. In the quiescent position anelastomer spring unit 87, 88 acts to resiliently deform the elastomerseal 79 against the surface of the ink supply unit 42.

When it is desired to operate the printhead unit, upon the insertion ofpaper, the solenoid coil 75 is activated so as to cause the arm 78 tomove down to be adjacent to the end plate 76. The arm 78 is held againstend plate 76 while the printhead is printing by means of a small “keepercurrent” in coil 75. Simulation results indicate that the keeper currentcan be significantly less than the actuation current. Subsequently,after photo printing, the paper is guillotined by the cutting mechanism63 of FIG. 8 acting against aluminum strip 43, and rewound so as toclear the area of the re-capping mechanism 80. Subsequently, the currentis turned off and springs 87, 88 return the arm 78 so that the elastomerseal is again resting against the printhead ink supply cartridge.

It can be seen that the preferred embodiment provides for a simple andinexpensive means of re-capping a printhead through the utilization of asolenoid type device having a long rectangular form. Further, thepreferred embodiment utilizes minimal power in that currents are onlyrequired whilst the device is operational and additionally, only a lowkeeper current is required whilst the printhead is printing.

Turning next to FIGS. 13 and 14, FIG. 13 illustrates an explodedperspective of the ink supply cartridge 42 whilst FIG. 14 illustrates aclose up sectional view of a bottom of the ink supply cartridge with theprinthead unit in place. The ink supply cartridge 42 is based around apagewidth printhead 102 which comprises a long slither of silicon havinga series of holes etched on the back surface for the supply of ink to afront surface of the silicon wafer for subsequent ejection via a microelectromechanical system. The form of ejection can be many differentforms such as those set out in the tables below.

Of course, many other inkjet technologies, as referred to the attachedtables below, can also be utilized when constructing a printhead unit102. The fundamental requirement of the ink supply cartridge 42 is thesupply of ink to a series of color channels etched through the backsurface of the printhead 102. In the description of the preferredembodiment, it is assumed that a three color printing process is to beutilized so as to provide full color picture output. Hence, the printsupply unit includes three ink supply reservoirs being a cyan reservoir104, a magenta reservoir 105 and a yellow reservoir 106. Each of thesereservoirs is required to store ink and includes a corresponding spongetype material 107-109 which assists in stabilizing ink within thecorresponding ink channel and inhibiting the ink from sloshing back andforth when the printhead is utilized in a handheld camera system. Thereservoirs 104, 105, 106 are formed through the mating of first exteriorplastic piece 110 and a second base piece 111.

At a first end 118 of the base piece 111 a series of air inlet 113-115are provided. Each air inlet leads to a corresponding winding channelwhich is hydrophobically treated so as to act as an ink repellent andtherefore repel any ink that may flow along the air inlet channel. Theair inlet channel further takes a convoluted path assisting in resistingany ink flow out of the chambers 104-106. An adhesive tape portion 117is provided for sealing the channels within end portion 118.

At the top end, there is included a series of refill holes (not shown)for refilling corresponding ink supply chambers 104, 105, 106. A plug121 is provided for sealing the refill holes.

Turning now to FIG. 14, there is illustrated a close up perspectiveview, partly in section through the ink supply cartridge 42 of FIG. 13when formed as a unit. The ink supply cartridge includes the three colorink reservoirs 104, 105, 106 which supply ink to different portions ofthe back surface of printhead 102 which includes a series of apertures128 defined therein for carriage of the ink to the front surface.

The ink supply cartridge 42 includes two guide walls 124, 125 whichseparate the various ink chambers and are tapered into an end portionabutting the surface of the printhead 102. The guide walls 124, 125 arefurther mechanically supported by block portions e.g. 126 which areplaced at regular intervals along the length of the ink supply unit. Theblock portions 126 have space at portions close to the back of printhead102 for the flow of ink around the back surface thereof.

The ink supply unit is preferably formed from a multi-part plasticinjection mold and the mold pieces e.g. 110, 111 (FIG. 13) snap togetheraround the sponge pieces 107, 109. Subsequently, a syringe type devicecan be inserted in the ink refill holes and the ink reservoirs filledwith ink with the air flowing out of the air outlets 113-115.Subsequently, the adhesive tape portion 117 and plug 121 are attachedand the printhead tested for operation capabilities. Subsequently, theink supply cartridge 42 can be readily removed for refilling by means ofremoving the ink supply cartridge, performing a washing cycle, and thenutilizing the holes for the insertion of a refill syringe filled withink for refilling the ink chamber before returning the ink supplycartridge 42 to a camera.

Turning now to FIG. 15, there is shown an example layout of the ImageCapture and Processing Chip (ICP) 48. The Image Capture and ProcessingChip 48 provides most of the electronic functionality of the camera withthe exception of the print head chip. The chip 48 is a highly integratedsystem. It combines CMOS image sensing, analog to digital conversion,digital image processing, DRAM storage, ROM, and miscellaneous controlfunctions in a single chip.

The chip is estimated to be around 32 mm² using a leading edge 0.18micron CMOS/DRAM/APS process. The chip size and cost can scale somewhatwith Moore's law, but is dominated by a CMOS active pixel sensor array201, so scaling is limited as the sensor pixels approach the diffractionlimit.

The ICP 48 includes CMOS logic, a CMOS image sensor, DRAM, and analogcircuitry. A very small amount of flash memory or other non-volatilememory is also preferably included for protection against reverseengineering.

Alternatively, the ICP can readily be divided into two chips: one forthe CMOS imaging array, and the other for the remaining circuitry. Thecost of this two chip solution should not be significantly differentthan the single chip ICP, as the extra cost of packaging and bond-padarea is somewhat cancelled by the reduced total wafer area requiring thecolor filter fabrication steps.

The ICP preferably contains the following functions:

Function 1.5 megapixel image sensor Analog Signal Processors Imagesensor column decoders Image sensor row decoders Analogue to DigitalConversion (ADC) Column ADC's Auto exposure 12 Mbits of DRAM DRAMAddress Generator Color interpolator Convolver Color ALU Halftone matrixROM Digital halftoning Print head interface 8 bit CPU core Program ROMFlash memory Scratchpad SRAM Parallel interface (8 bit) Motor drivetransistors (5) Clock PLL JTAG test interface Test circuits Busses Bondpads

The CPU, DRAM, Image sensor, ROM, Flash memory, Parallel interface, JTAGinterface and ADC can be vendor supplied cores. The ICP is intended torun on 1.5V to minimize power consumption and allow convenient operationfrom two AA type battery cells.

FIG. 15 illustrates a layout of the ICP 48. The ICP 48 is dominated bythe imaging array 201, which consumes around 80% of the chip area. Theimaging array is a CMOS 4 transistor active pixel design with aresolution of 1,500×1,000. The array can be divided into theconventional configuration, with two green pixels, one red pixel, andone blue pixel in each pixel group. There are 750×500 pixel groups inthe imaging array.

The latest advances in the field of image sensing and CMOS image sensingin particular can be found in the October, 1997 issue of IEEETransactions on Electron Devices and, in particular, pages 1689 to 1968.Further, a specific implementation similar to that disclosed in thepresent application is disclosed in Wong et al., “CMOS Active PixelImage Sensors Fabricated Using a 1.8V, 0.25 μm CMOS Technology”, IEDM1996, page 915

The imaging array uses a 4 transistor active pixel design of a standardconfiguration. To minimize chip area and therefore cost, the imagesensor pixels should be as small as feasible with the technologyavailable. With a four transistor cell, the typical pixel size scales as20 times the lithographic feature size. This allows a minimum pixel areaof around 3.6 μm×3.6 μm. However, the photosite must be substantiallyabove the diffraction limit of the lens. It is also advantageous to havea square photosite, to maximize the margin over the diffraction limit inboth horizontal and vertical directions. In this case, the photosite canbe specified as 2.5 μm×2.5 μm. The photosite can be a photogate, pinnedphotodiode, charge modulation device, or other sensor.

The four transistors are packed as an ‘L’ shape, rather than arectangular region, to allow both the pixel and the photosite to besquare. This reduces the transistor packing density slightly, increasingpixel size. However, the advantage in avoiding the diffraction limit isgreater than the small decrease in packing density.

The transistors also have a gate length which is longer than the minimumfor the process technology. These have been increased from a drawnlength of 0.18 micron to a drawn length of 0.36 micron. This is toimprove the transistor matching by making the variations in gate lengthrepresent a smaller proportion of the total gate length.

The extra gate length, and the ‘L’ shaped packing, mean that thetransistors use more area than the minimum for the technology. Normally,around 8 μm² would be required for rectangular packing. Preferably, 9.75μm² has been allowed for the transistors.

The total area for each pixel is 16 μm², resulting from a pixel size of4 μm×4 μm. With a resolution of 1,500×1,000, the area of the imagingarray 101 is 6,000 μm×4,000 μm, or 24 mm².

The presence of a color image sensor on the chip affects the processrequired in two major ways:

-   -   The CMOS fabrication process should be optimised to minimize        dark current

Color filters are required. These can be fabricated using dyedphotosensitive polyimides, resulting in an added process complexity ofthree spin coatings, three photolithographic steps, three developmentsteps, and three hardbakes.

There are 15,000 analog signal processors (ASPs) 205, one for each ofthe columns of the sensor. The ASPs amplify the signal, provide a darkcurrent reference, sample and hold the signal, and suppress the fixedpattern noise (FPN).

There are 375 analog to digital converters 206, one for each fourcolumns of the sensor array. These may be delta-sigma or successiveapproximation type ADC's. A row of low column ADC's are used to reducethe conversion speed required, and the amount of analog signaldegradation incurred before the signal is converted to digital. Thisalso eliminates the hot spot (affecting local dark current) and thesubstrate coupled noise that would occur if a single high speed ADC wasused. Each ADC also has two four bit DAC's which trim the offset andscale of the ADC to further reduce FPN variations between columns. TheseDAC's are controlled by data stored in flash memory during chip testing.

The column select logic 204 is a 1:1500 decoder which enables theappropriate digital output of the ADCs onto the output bus. As each ADCis shared by four columns, the least significant two bits of the rowselect control 4 input analog multiplexors.

A row decoder 207 is a 1:1000 decoder which enables the appropriate rowof the active pixel sensor array. This selects which of the 1000 rows ofthe imaging array is connected to analog signal processors. As the rowsare always accessed in sequence, the row select logic can be implementedas a shift register.

An auto exposure system 208 adjusts the reference voltage of the ADC 205in response to the maximum intensity sensed during the previous frameperiod. Data from the green pixels is passed through a digital peakdetector. The peak value of the image frame period before capture (thereference frame) is provided to a digital to analogue converter (DAC),which generates the global reference voltage for the column ADCs. Thepeak detector is reset at the beginning of the reference frame. Theminimum and maximum values of the three RGB color components are alsocollected for color correction.

The second largest section of the chip is consumed by a DRAM 210 used tohold the image. To store the 1,500×1,000 image from the sensor withoutcompression, 1.5 Mbytes of DRAM 210 are required. This equals 12 Mbits,or slightly less than 5% of a 256 Mbit DRAM. The DRAM technology assumedis of the 256 Mbit generation implemented using 0.18 μm CMOS.

Using a standard 8F cell, the area taken by the memory array is 3.11mm². When row decoders, column sensors, redundancy, and other factorsare taken into account, the DRAM requires around 4 mm².

This DRAM 210 can be mostly eliminated if analog storage of the imagesignal can be accurately maintained in the CMOS imaging array for thetwo seconds required to print the photo. However, digital storage of theimage is preferable as it is maintained without degradation, isinsensitive to noise, and allows copies of the photo to be printedconsiderably later.

A DRAM address generator 211 provides the write and read addresses tothe DRAM 210. Under normal operation, the write address is determined bythe order of the data read from the CMOS image sensor 201. This willtypically be a simple raster format. However, the data can be read fromthe sensor 201 in any order, if matching write addresses to the DRAM aregenerated. The read order from the DRAM 210 will normally simply matchthe requirements of a color interpolator and the print head. As thecyan, magenta, and yellow rows of the print head are necessarily offsetby a few pixels to allow space for nozzle actuators, the colors are notread from the DRAM simultaneously. However, there is plenty of time toread all of the data from the DRAM many times during the printingprocess. This capability is used to eliminate the need for FIFOs in theprint head interface, thereby saving chip area. All three RGB imagecomponents can be read from the DRAM each time color data is required.This allows a color space converter to provide a more sophisticatedconversion than a simple linear RGB to CMY conversion.

Also, to allow two dimensional filtering of the image data withoutrequiring line buffers, data is re-read from the DRAM array.

The address generator may also implement image effects in certain modelsof camera. For example, passport photos are generated by a manipulationof the read addresses to the DRAM. Also, image framing effects (wherethe central image is reduced), image warps, and kaleidoscopic effectscan all be generated by manipulating the read addresses of the DRAM.

While the address generator 211 may be implemented with substantialcomplexity if effects are built into the standard chip, the chip arearequired for the address generator is small, as it consists only ofaddress counters and a moderate amount of random logic.

A color interpolator 214 converts the interleaved pattern of red,2×green, and blue pixels into RGB pixels. It consists of three 8 bitadders and associated registers. The divisions are by either 2 (forgreen) or 4 (for red and blue) so they can be implemented as fixedshifts in the output connections of the adders.

A convolver 215 is provided as a sharpening filter which applies a smallconvolution kernel (5×5) to the red, green, and blue planes of theimage. The convolution kernel for the green plane is different from thatof the red and blue planes, as green has twice as many samples. Thesharpening filter has five functions:

-   -   to improve the color interpolation from the linear interpolation        provided by the color interpolator, to a close approximation of        a sinc interpolation;    -   to compensate for the image ‘softening’ which occurs during        digitisation;    -   to adjust the image sharpness to match average consumer        preferences, which are typically for the image to be slightly        sharper than reality. As the single use camera is intended as a        consumer product, and not a professional photographic products,        the processing can match the most popular settings, rather than        the most accurate;    -   to suppress the sharpening of high frequency (individual pixel)        noise. The function is similar to the ‘unsharp mask’ process;        and    -   to antialias Image Warping.

These functions are all combined into a single convolution matrix. Asthe pixel rate is low (less than 1 Mpixel per second) the total numberof multiplies required for the three color channels is 56 millionmultiplies per second. This can be provided by a single multiplier.Fifty bytes of coefficient ROM are also required.

A color ALU 113 combines the functions of color compensation and colorspace conversion into the one matrix multiplication, which is applied toevery pixel of the frame. As with sharpening, the color correctionshould match the most popular settings, rather than the most accurate.

A color compensation circuit of the color ALU provides compensation forthe lighting of the photo. The vast majority of photographs aresubstantially improved by a simple color compensation, whichindependently normalizes the contrast and brightness of the three colorcomponents.

A color look-up table (CLUT) 212 is provided for each color component.These are three separate 256×8 SRAMs, requiring a total of 6,144 bits.The CLUTs are used as part of the color correction process. They arealso used for color special effects, such as stochastically selected“wild color” effects.

A color space conversion system of the color ALU converts from the RGBcolor space of the image sensor to the CMY color space of the printer.The simplest conversion is a 1's complement of the RGB data. However,this simple conversion assumes perfect linearity of both color spaces,and perfect dye spectra for both the color filters of the image sensor,and the ink dyes. At the other extreme is a tri-linear interpolation ofa sampled three dimensional arbitrary transform table. This caneffectively match any non-linearity or differences in either colorspace. Such a system is usually necessary to obtain good color spaceconversion when the print engine is a color electrophotographic

However, since the non-linearity of a halftoned ink jet output is verysmall, a simpler system can be used. A simple matrix multiply canprovide excellent results. This requires nine multiplies and sixadditions per contone pixel. However, since the contone pixel rate islow (less than 1 Mpixel/sec) these operations can share a singlemultiplier and adder. The multiplier and adder are used in a color ALUwhich is shared with the color compensation function.

Digital halftoning can be performed as a dispersed dot ordered ditherusing a stochastic optimized dither cell. A halftone matrix ROM 216 isprovided for storing dither cell coefficients. A dither cell size of32×32 is adequate to ensure that the cell repeat cycle is not visible.The three colors—cyan, magenta, and yellow—are all dithered using thesame cell, to ensure maximum co-positioning of the ink dots. Thisminimizes ‘muddying’ of the mid-tones which results from bleed of dyesfrom one dot to adjacent dots while still wet. The total ROM sizerequired is 1 KByte, as the one ROM is shared by the halftoning unitsfor each of the three colors.

The digital halftoning used is dispersed dot ordered dither withstochastic optimized dither matrix. While dithering does not produce animage quite as ‘sharp’ as error diffusion, it does produce a moreaccurate image with fewer artifacts. The image sharpening produced byerror diffusion is artificial, and less controllable and accurate than‘unsharp mask’ filtering performed in the contone domain. The high printresolution (1,600 dpi×1,600 dpi) results in excellent quality when usinga well formed stochastic dither matrix.

Digital halftoning is performed by a digital halftoning unit 217 using asimple comparison between the contone information from the DRAM 210 andthe contents of the dither matrix 216. During the halftone process, theresolution of the image is changed from the 250 dpi of the capturedcontone image to the 1,600 dpi of the printed image. Each contone pixelis converted to an average of 40.96 halftone dots.

The ICP incorporates a 16 bit microcontroller CPU core 219 to run themiscellaneous camera functions, such as reading the buttons, controllingthe motor and solenoids, setting up the hardware, and authenticating therefill station. The processing power required by the CPU is very modest,and a wide variety of processor cores can be used. As the entire CPUprogram is run from a small ROM 220 program compatibility between cameraversions is not important, as no external programs are run. A 2 Mbit(256 Kbyte) program and data ROM 220 is included on chip. Most of thisROM space is allocated to data for outline graphics and fonts forspecialty cameras. The program requirements are minor. The single mostcomplex task is the encrypted authentication of the refill station. TheROM requires a single transistor per bit.

A Flash memory 221 may be used to store a 128 bit authentication code.This provides higher security than storage of the authentication code inROM, as reverse engineering can be made essentially impossible. TheFlash memory is completely covered by third level metal, making the dataimpossible to extract using scanning probe microscopes or electronbeams. The authentication code is stored in the chip when manufactured.At least two other Flash bits are required for the authenticationprocess: a bit which locks out reprogramming of the authentication code,and a bit which indicates that the camera has been refilled by anauthenticated refill station. The flash memory can also be used to storeFPN correction data for the imaging array. Additionally, a phase lockedloop rescaling parameter is stored for scaling the clocking cycle to anappropriate correct time. The clock frequency does not require crystalaccuracy since no date functions are provided. To eliminate the cost ofa crystal, an on chip oscillator with a phase locked loop 224 is used.As the frequency of an on-chip oscillator is highly variable from chipto chip, the frequency ratio of the oscillator to the PLL is digitallytrimmed during initial testing. The value is stored in Flash memory 221.This allows the clock PLL to control the ink-jet heater pulse width withsufficient accuracy.

A scratchpad SRAM is a small static RAM 222 with a 6T cell. Thescratchpad provided temporary memory for the 16 bit CPU. 1024 bytes isadequate.

A print head interface 223 formats the data correctly for the printhead. The print head interface also provides all of the timing signalsrequired by the print head. These timing signals may vary depending upontemperature, the number of dots printed simultaneously, the print mediumin the print roll, and the dye density of the ink in the print roll.

The following is a table of external connections to the print headinterface:

Connection Function Pins DataBits[0-7] Independent serial data to theeight 8 segments of the printhead BitClock Main data clock for the printhead 1 ColorEnable[0-2] Independent enable signals for the 3 CMYactuators, allowing different pulse times for each color.BankEnable[0-1] Allows either simultaneous or 2 interleaved actuation oftwo banks of nozzles. This allows two different print speed/powerconsumption tradeoffs NozzleSelect[0-4] Selects one of 32 banks ofnozzles 5 for simultaneous actuation ParallelXferClock Loads theparallel transfer register 1 with the data from the shift registersTotal 20

The printhead utilized is composed of eight identical segments, each1.25 cm long. There is no connection between the segments on the printhead chip. Any connections required are made in the external TAB bondingfilm, which is double sided. The division into eight identical segmentsis to simplify lithography using wafer steppers. The segment width of1.25 cm fits easily into a stepper field. As the printhead chip is longand narrow (10 cm×0.3 mm), the stepper field contains a single segmentof 32 print head chips. The stepper field is therefore 1.25 cm×1.6 cm.An average of four complete print heads are patterned in each waferstep.

A single BitClock output line connects to all 8 segments on theprinthead. The 8 DataBits lines lead one to each segment, and areclocked into the 8 segments on the print head simultaneously (on aBitClock pulse). For example, dot 0 is transferred to segment₀, dot 750is transferred to segment₁, dot 1500 to segment₂ etc simultaneously.

The ParallelXferClock is connected to each of the 8 segments on theprinthead, so that on a single pulse, all segments transfer their bitsat the same time.

The NozzleSelect, BankEnable and ColorEnable lines are connected to eachof the 8 segments, allowing the print head interface to independentlycontrol the duration of the cyan, magenta, and yellow nozzle energizingpulses. Registers in the Print Head Interface allow the accuratespecification of the pulse duration between 0 and 6 ms, with a typicalduration of 2 ms to 3 ms.

A parallel interface 125 connects the ICP to individual staticelectrical signals. The CPU is able to control each of these connectionsas memory mapped I/O via a low speed bus.

The following is a table of connections to the parallel interface:

Connection Direction Pins Paper transport stepper motor Output 4 Cappingsolenoid Output 1 Copy LED Output 1 Photo button Input 1 Copy buttonInput 1 Total 8

Seven high current drive transistors e.g. 227 are required. Four are forthe four phases of the main stepper motor two are for the guillotinemotor, and the remaining transistor is to drive the capping solenoid.These transistors are allocated 20,000 square microns (600,000 F) each.As the transistors are driving highly inductive loads, they must eitherbe turned off slowly, or be provided with a high level of back EMFprotection. If adequate back EMF protection cannot be provided using thechip process chosen, then external discrete transistors should be used.The transistors are never driven at the same time as the image sensor isused. This is to avoid voltage fluctuations and hot spots affecting theimage quality. Further, the transistors are located as far away from thesensor as possible.

A standard JTAG (Joint Test Action Group) interface 228 is included inthe ICP for testing purposes and for interrogation by the refillstation. Due to the complexity of the chip, a variety of testingtechniques are required, including BIST (Built In Self Test) andfunctional block isolation. An overhead of 10% in chip area is assumedfor chip testing circuitry for the random logic portions. The overheadfor the large arrays the image sensor and the DRAM is smaller.

The JTAG interface is also used for authentication of the refillstation. This is included to ensure that the cameras are only refilledwith quality paper and ink at a properly constructed refill station,thus preventing inferior quality refills from occurring. The camera mustauthenticate the refill station, rather than vice versa. The secureprotocol is communicated to the refill station during the automated testprocedure. Contact is made to four gold plated spots on the ICP/printhead TAB by the refill station as the new ink is injected into the printhead.

FIG. 16 illustrates a rear view of the next step in the constructionprocess whilst FIG. 17 illustrates a front view.

Turning now to FIG. 16, the assembly of the camera system proceeds viafirst assembling the ink supply mechanism 40. The flex PCB isinterconnected with batteries 84, only one of which is shown, which areinserted in the middle portion of a print roll 85 which is wrappedaround a plastic former 86. An end cap 89 is provided at the other endof the print roll 85 so as to fasten the print roll and batteries firmlyto the ink supply mechanism.

The solenoid coil is interconnected (not shown) to interconnects 97, 98(FIG. 8) which include leaf spring ends for interconnection withelectrical contacts on the Flex PCB so as to provide for electricalcontrol of the solenoid.

Turning now to FIGS. 17-19 the next step in the construction process isthe insertion of the relevant gear trains into the side of the camerachassis. FIG. 17 illustrates a front view, FIG. 18 illustrates a rearview and FIG. 19 also illustrates a rear view. The first gear traincomprising gear wheels 22, 23 is utilized for driving the guillotineblade with the gear wheel 23 engaging the gear wheel 65 of FIG. 8. Thesecond gear train comprising gear wheels 24, 25 and 26 engage one end ofthe print roller 61 of FIG. 8. As best indicated in FIG. 18, the gearwheels mate with corresponding pins on the surface of the chassis withthe gear wheel 26 being snap fitted into corresponding mating hole 27.

Next, as illustrated in FIG. 20, the assembled platten unit 60 is theninserted between the print roll 85 and aluminum cutting blade 43.

Turning now to FIG. 21, by way of illumination, there is illustrated theelectrically interactive components of the camera system. As notedpreviously, the components are based around a Flex PCB board and includea TAB film 58 which interconnects the printhead 102 with the imagesensor and processing chip 48. Power is supplied by two AA typebatteries 83, 84 and a paper drive stepper motor 16 is provided inaddition to a rotary guillotine motor 17.

An optical element 31 is provided for snapping into a top portion of thechassis 12. The optical element 31 includes portions defining an opticalview finder 32, 33 which are slotted into mating portions 35, 36 in viewfinder channel 37. Also provided in the optical element 31 is a lensingsystem 38 for magnification of the prints left number in addition to anoptical pipe element 39 for piping light from the LED 5 for externaldisplay.

Turning next to FIG. 22, the assembled unit 90 is then inserted into afront outer case 91 which includes button 4 for activation of printouts.

Turning now to FIG. 23, next, the unit 90 is provided with a snap-onback cover 93 which includes a slot 6 and copy print button 7. A wrapperlabel containing instructions and advertising (not shown) is thenwrapped around the outer surface of the camera system and pinch clampedto the cover by means of clamp strip 96 which can comprise a flexibleplastic or rubber strip.

Subsequently, the preferred embodiment is ready for use as a one timeuse camera system that provides for instant output images on demand. Itwill be evident that the preferred embodiment further provides for arefillable camera system. A used camera can be collected and its outerplastic cases removed and recycled. A new paper roll and batteries canbe added and the ink cartridge refilled. A series of automatic testroutines can then be carried out to ensure that the printer is properlyoperational. Further, in order to ensure only authorized refills areconducted so as to enhance quality, routines in the on-chip program ROMcan be executed such that the camera authenticates the refilling stationusing a secure protocol. Upon authentication, the camera can reset aninternal paper count and an external case can be fitted on the camerasystem with a new outer label. Subsequent packing and shipping can thentake place.

It will be further readily evident to those skilled in the art that theprogram ROM can be modified so as to allow for a variety of digitalprocessing routines. In addition to the digitally enhanced photographsoptimized for mainstream consumer preferences, various other models canreadily be provided through mere re-programming of the program ROM. Forexample, a sepia classic old fashion style output can be providedthrough a remapping of the color mapping function. A further alternativeis to provide for black and white outputs again through a suitable colorremapping algorithm. Minimum color can also be provided to add a touchof color to black and white prints to produce the effect that wastraditionally used to colorize black and white photos. Further, passportphoto output can be provided through suitable address remappings withinthe address generators. Further, edge filters can be utilized as isknown in the field of image processing to produce sketched art styles.Further, classic wedding borders and designs can be placed around anoutput image in addition to the provision of relevant clip arts. Forexample, a wedding style camera might be provided. Further, a panoramicmode can be provided so as to output the well known panoramic format ofimages. Further, a postcard style output can be provided through theprinting of postcards including postage on the back of a print rollsurface. Further, cliparts can be provided for special events such asHalloween, Christmas etc. Further, kaleidoscopic effects can be providedthrough address remappings and wild color effects can be providedthrough remapping of the color lookup table. Many other forms of specialevent cameras can be provided for example, cameras dedicated to theOlympics, movie tie-ins, advertising and other special events.

The operational mode of the camera can be programmed so that upon thedepressing of the take photo a first image is sampled by the sensorarray to determine irrelevant parameters. Next a second image is againcaptured which is utilized for the output. The captured image is thenmanipulated in accordance with any special requirements before beinginitially output on the paper roll. The LED light is then activated fora predetermined time during which the DRAM is refreshed so as to retainthe image. If the print copy button is depressed during thispredetermined time interval, a further copy of the photo is output.After the predetermined time interval where no use of the camera hasoccurred, the onboard CPU shuts down all power to the camera systemuntil such time as the take button is again activated. In this way,substantial power savings can be realized.

Ink Jet Technologies

The embodiments of the invention use an ink jet printer type device. Ofcourse many different devices could be used. However presently popularink jet printing technologies are unlikely to be suitable.

The most significant problem with thermal inkjet is power consumption.This is approximately 100 times that required for high speed, and stemsfrom the energy-inefficient means of drop ejection. This involves therapid boiling of water to produce a vapor bubble which expels the ink.Water has a very high heat capacity, and must be superheated in thermalinkjet applications. This leads to an efficiency of around 0.02%, fromelectricity input to drop momentum (and increased surface area) out.

The most significant problem with piezoelectric inkjet is size and cost.Piezoelectric crystals have a very small deflection at reasonable drivevoltages, and therefore require a large area for each nozzle. Also, eachpiezoelectric actuator must be connected to its drive circuit on aseparate substrate. This is not a significant problem at the currentlimit of around 300 nozzles per print head, but is a major impediment tothe fabrication of pagewidth print heads with 19,200 nozzles.

Ideally, the inkjet technologies used meet the stringent requirements ofin-camera digital color printing and other high quality, high speed, lowcost printing applications. To meet the requirements of digitalphotography, new inkjet technologies have been created. The targetfeatures include:

-   -   low power (less than 10 Watts)    -   high resolution capability (1,600 dpi or more)    -   photographic quality output    -   low manufacturing cost    -   small size (pagewidth times minimum cross section)    -   high speed (<2 seconds per page).

All of these features can be met or exceeded by the inkjet systemsdescribed below with differing levels of difficulty. forty-fivedifferent inkjet technologies have been developed by the Assignee togive a wide range of choices for high volume manufacture. Thesetechnologies form part of separate applications assigned to the presentAssignee as set out in the table below.

The inkjet designs shown here are suitable for a wide range of digitalprinting systems, from battery powered one-time use digital cameras,through to desktop and network printers, and through to commercialprinting systems

For ease of manufacture using standard process equipment, the printheadis designed to be a monolithic 0.5 micron CMOS chip with MEMS postprocessing. For color photographic applications, the print head is 100mm long, with a width which depends upon the inkjet type. The smallestprint head designed is IJ38, which is 0.35 mm wide, giving a chip areaof 35 square mm. The print heads each contain 19,200 nozzles plus dataand control circuitry.

Ink is supplied to the back of the print head by injection moldedplastic ink channels. The molding requires 50 micron features, which canbe created using a lithographically micromachined insert in a standardinjection molding tool. Ink flows through holes etched through the waferto the nozzle chambers fabricated on the front surface of the wafer. Theprint head is connected to the camera circuitry by tape automatedbonding.

Cross-Referenced Applications

The following table is a guide to cross-referenced patent applicationsfiled concurrently herewith and discussed hereinafter with the referencebeing utilized in subsequent tables when referring to a particular case:

Docket No. Reference Title IJ01US IJ01 Radiant Plunger Ink Jet PrinterIJ02US IJ02 Electrostatic Ink Jet Printer IJ03US IJ03 PlanarThermoelastic Bend Actuator Ink Jet IJ04US IJ04 Stacked ElectrostaticInk Jet Printer IJ05US IJ05 Reverse Spring Lever Ink Jet Printer IJ06USIJ06 Paddle Type Ink Jet Printer IJ07US IJ07 Permanent MagnetElectromagnetic Ink Jet Printer IJ08US IJ08 Planar Swing GrillElectromagnetic Ink Jet Printer IJ09US IJ09 Pump Action Refill Ink JetPrinter IJ10US IJ10 Pulsed Magnetic Field Ink Jet Printer IJ11US IJ11Two Plate Reverse Firing Electromagnetic Ink Jet Printer IJ12US IJ12Linear Stepper Actuator Ink Jet Printer IJ13US IJ13 Gear Driven ShutterInk Jet Printer IJ14US IJ14 Tapered Magnetic Pole Electromagnetic InkJet Printer IJ15US IJ15 Linear Spring Electromagnetic Grill Ink JetPrinter IJ16US IJ16 Lorenz Diaphragm Electromagnetic Ink Jet PrinterIJ17US IJ17 PTFE Surface Shooting Shuttered Oscillating Pressure Ink JetPrinter IJ18US IJ18 Buckle Grip Oscillating Pressure Ink Jet PrinterIJ19US IJ19 Shutter Based Ink Jet Printer IJ20US IJ20 Curling CalyxThermoelastic Ink Jet Printer IJ21US IJ21 Thermal Actuated Ink JetPrinter IJ22US IJ22 Iris Motion Ink Jet Printer IJ23US IJ23 DirectFiring Thermal Bend Actuator Ink Jet Printer IJ24US IJ24 Conductive PTFEBen Activator Vented Ink Jet Printer IJ25US IJ25 Magnetostrictive InkJet Printer IJ26US IJ26 Shape Memory Alloy Ink Jet Printer IJ27US IJ27Buckle Plate Ink Jet Printer IJ28US IJ28 Thermal Elastic Rotary ImpellerInk Jet Printer IJ29US IJ29 Thermoelastic Bend Actuator Ink Jet PrinterIJ30US IJ30 Thermoelastic Bend Actuator Using PTFE and Corrugated CopperInk Jet Printer IJ31US IJ31 Bend Actuator Direct Ink Supply Ink JetPrinter IJ32US IJ32 A High Young's Modulus Thermoelastic Ink Jet PrinterIJ33US IJ33 Thermally actuated slotted chamber wall ink jet printerIJ34US IJ34 Ink Jet Printer having a thermal actuator comprising anexternal coiled spring IJ35US IJ35 Trough Container Ink Jet PrinterIJ36US IJ36 Dual Chamber Single Vertical Actuator Ink Jet IJ37US IJ37Dual Nozzle Single Horizontal Fulcrum Actuator Ink Jet IJ38US IJ38 DualNozzle Single Horizontal Actuator Ink Jet IJ39US IJ39 A single bendactuator cupped paddle ink jet printing device IJ40US IJ40 A thermallyactuated ink jet printer having a series of thermal actuator unitsIJ41US IJ41 A thermally actuated ink jet printer including a taperedheater element IJ42US IJ42 Radial Back-Curling Thermoelastic Ink JetIJ43US IJ43 Inverted Radial Back-Curling Thermoelastic Ink Jet IJ44USIJ44 Surface bend actuator vented ink supply ink jet printer IJ45US IJ45Coil Acutuated Magnetic Plate Ink Jet PrinterTables of Drop-on-Demand Inkjets

Eleven important characteristics of the fundamental operation ofindividual inkjet nozzles have been identified. These characteristicsare largely orthogonal, and so can be elucidated as an elevendimensional matrix. Most of the eleven axes of this matrix includeentries developed by the present assignee.

The following tables form the axes of an eleven dimensional table ofinkjet types.

-   -   Actuator mechanism (18 types)    -   Basic operation mode (7 types)    -   Auxiliary mechanism (8 types)    -   Actuator amplification or modification method (17 types)    -   Actuator motion (19 types)    -   Nozzle refill method (4 types)    -   Method of restricting back-flow through inlet (10 types)    -   Nozzle clearing method (9 types)    -   Nozzle plate construction (9 types)    -   Drop ejection direction (5 types)    -   Ink type (7 types)

The complete eleven dimensional table represented by these axes contains36.9 billion possible configurations of inkjet nozzle. While not all ofthe possible combinations result in a viable inkjet technology, manymillion configurations are viable. It is clearly impractical toelucidate all of the possible configurations. Instead, certain inkjettypes have been investigated in detail. These are designated IJ01 toIJ45 above.

Other inkjet configurations can readily be derived from these forty-fiveexamples by substituting alternative configurations along one or more ofthe eleven axes. Most of the IJ01 to IJ45 examples can be made intoinkjet print heads with characteristics superior to any currentlyavailable inkjet technology.

Where there are prior art examples known to the inventor, one or more ofthese examples are listed in the examples column of the tables below.The IJ01 to IJ45 series are also listed in the examples column. In somecases, a printer may be listed more than once in a table, where itshares characteristics with more than one entry.

Suitable applications include: Home printers, Office network printers,Short run digital printers, Commercial print systems, Fabric printers,Pocket printers, Internet WWW printers, Video printers, Medical imaging,Wide format printers, Notebook PC printers, Fax machines, Industrialprinting systems, Photocopiers, Photographic minilabs etc.

The information associated with the aforementioned eleven dimensionalmatrix are set out in the following tables.

ACTUATOR MECHANISM (APPLIED ONLY TO SELECTED INK DROPS) ActuatorMechanism Description Advantages Disadvantages Examples Thermal bubbleAn electrothermal heater Large force generated High power CanonBubblejet 1979 heats the ink to Simple construction Ink carrier limitedEndo et al GB patent above boiling point, No moving parts to water2,007,162 transferring significant Fast operation Low efficiency Xeroxheater-in-pit 1990 heat to the aqueous ink. Small chip area required forHigh temperatures Hawkins et al U.S. Pat. No. A bubble nucleates andactuator required 4,899,181 quickly forms, expelling High mechanicalHewlett-Packard TIJ the ink. The efficiency stress 1982 Vaught et al ofthe process is low, Unusual materials U.S. Pat. No. 4,490,728 withtypically less than required 0.05% of the electrical Large drive energybeing transformed transistors into kinetic energy of Cavitation causesthe drop. actuator failure Kogation reduces bubble formation Large printheads are difficult to fabricate Piezoelectric A piezoelectric Low powerconsumption Very large area Kyser et al U.S. Pat. No. crystal such aslead Many ink types can be used required for 3,946,398 lanthanumzirconate Fast operation actuator Zoltan U.S. Pat. No. 3,683,212 (PZT)is electrically High efficiency Difficult to 1973 Stemme U.S. Pat. No.activated, and either integrate with 3,747,120 expands, shears, orelectronics Epson Stylus bends to apply pressure High voltage driveTektronix to the ink, ejecting transistors required IJ04 drops. Fullpagewidth print heads impractical due to actuator size Requireselectrical poling in high field strengths during manufactureElectro-strictive An electric field is Low power consumption Low maximumstrain Seiko Epson, Usui et all used to activate Many ink types can beused (approx. 0.01%) JP 253401/96 electrostriction in Low thermalexpansion Large area required IJ04 relaxor materials such Electric fieldstrength required for actuator due to as lead lanthanum (approx. 3.5V/μm) can be low strain zirconate titanate generated without difficultyResponse speed is (PLZT) or lead Does not require electrical marginal(~10 μs) magnesium niobate poling High voltage drive (PMN). transistorsrequired Full pagewidth print heads impractical due to actuator sizeFerroelectric An electric field is Low power consumption Difficult toIJ04 used to induce a Many ink types can be used integrate with phasetransition Fast operation (<1 μs) electronics between the Relativelyhigh longitudinal Unusual materials antiferroelectric strain such asPLZSnT are (AFE) and ferroelectric High efficiency required (FE) phase.Perovskite Electric field strength of around Actuators require materialssuch as 3 V/μm can be readily a large area tin modified lead providedlanthanum zirconate titanate (PLZSnT) exhibit large strains of up to 1%associated with the AFE to FE phase transition. Electrostatic Conductiveplates are Low power consumption Difficult to operate IJ02, IJ04 platesseparated by a Many ink types can be used electrostatic devicescompressible or fluid Fast operation in an aqueous dielectric (usuallyenvironment air). Upon application The electrostatic of a voltage, theactuator will normally plates attract each need to be separated otherand displace ink, from the ink causing drop ejection. Very large areaThe conductive plates required to achieve may be in a comb or highforces honeycomb structure, or High voltage drive stacked to increasethe transistors may be surface area and required therefore the force.Full pagewidth print heads are not competitive due to actuator sizeElectrostatic pull A strong electric field Low current consumption Highvoltage required 1989 Saito et al, U.S. Pat. No. on ink is applied tothe Low temperature May be damaged by 4,799,068 ink, whereupon sparksdue to air 1989 Miura et al, U.S. Pat. No. electrostatic attractionbreakdown 4,810,954 accelerates the ink Required field Tone-jet towardsthe print strength increases medium. as the drop size decreases Highvoltage drive transistors required Electrostatic field attracts dustPermanent An electromagnet Low power consumption Complex fabricationIJ07, IJ10 magnet electro- directly attracts a Many ink types can beused Permanent magnetic magnetic permanent magnet, Fast operationmaterial such as displacing ink and High efficiency Neodymium Iron Boroncausing drop ejection. Easy extension from single (NdFeB) required. Rareearth magnets nozzles to pagewidth print High local currents with afield strength heads required around 1 Tesla can be Copper metalizationused. Examples are: should be used for Samarium Cobalt longelectromigration (SaCo) and magnetic lifetime and low materials in theresistivity neodymium iron boron Pigmented inks are family (NdFeB,usually infeasible NdDyFeBNb, NdDyFeB, etc) Operating temperaturelimited to the Curie temperature (around 540 K) Soft magnetic core Asolenoid induced a Low power consumption Complex fabrication IJ01, IJ05,IJ08, IJ10 electro-magnetic magnetic field in a Many ink types can beused Materials not usually IJ12, IJ14, IJ15, IJ17 soft magnetic core orFast operation present in a CMOS fab yoke fabricated from a Highefficiency such as NiFe, CoNiFe, ferrous material such as Easy extensionfrom single or CoFe are electroplated iron nozzles to pagewidth printrequired alloys such as CoNiFe heads High local currents [1], CoFe, orNiFe required alloys. Typically, the Copper metalization soft magneticmaterial should be used for is in two parts, long electromigration whichare normally held lifetime and low apart by a spring. When resistivitythe solenoid is actuated, Electroplating is the two parts attract,required displacing the ink. High saturation flux density is required(2.0-2.1 T is achievable with CoNiFe [1]) Magnetic The Lorenz forceacting Low power consumption Force acts as a IJ06, IJ11, IJ13, IJ16Lorenz force on a current carrying Many ink types can be used twistingmotion wire in a magnetic field Fast operation Typically, only a isutilized. High efficiency quarter of the sole- This allows the Easyextension from single noid length provides magnetic field to be nozzlesto pagewidth print force in a useful supplied externally to headsdirection the print head, for High local currents example with rareearth required permanent magnets. Copper metalization Only the currentshould be used for carrying wire need be long electromigrationfabricated on the print- lifetime and low head, simplifying resistivitymaterials requirements. Pigmented inks are usually infeasibleMagneto-striction The actuator uses the Many ink types can be used Forceacts as a Fischenbeck, U.S. Pat. No. giant magnetostrictive Fastoperation twisting motion 4,032,929 effect of materials such Easyextension from single Unusual materials IJ25 as Terfenol-D (an nozzlesto pagewidth print such as Terfenol-D alloy of terbium, heads arerequired dysprosium and iron High force is available High local currentsdeveloped at the required Naval Ordnance Copper metalization Laboratory,hence Ter- should be used for Fe-NOL). For best long electromigrationefficiency, the lifetime and low actuator should be resistivitypre-stressed to Pre-stressing may approx. 8 MPa. be required Surfacetension Ink under positive Low power consumption Requires supplementarySilverbrook, EP 0771 reduction pressure is held in Simple constructionforce to effect drop 658 A2 and related a nozzle by surface No unusualmaterials required separation patent applications tension. The surfacein fabrication Requires special ink tension of the ink is Highefficiency surfactants reduced below the Easy extension from singleSpeed may be limited bubble threshold, nozzles to pagewidth print bysurfactant causing the ink to heads properties egress from the nozzle.Viscosity The ink viscosity is Simple construction Requiressupplementary Silverbrook, EP 0771 reduction locally reduced to Nounusual materials required force to effect drop 658 A2 and relatedselect which drops in fabrication separation patent applications are tobe ejected. A Easy extension from single Requires special ink viscosityreduction nozzles to pagewidth print viscosity properties can beachieved heads High speed is electrothermally with difficult to achievemost inks, but Requires oscillating special inks can be ink pressureengineered for a 100:1 A high temperature viscosity reduction.difference (typically 80 degrees) is required Acoustic An acoustic waveis Can operate without a nozzle Complex drive circuitry 1993 Hadimiogluet al, generated and plate Complex fabrication EUP 550,192 focussed uponthe Low efficiency 1993 Elrod et al, EUP drop ejection region. Poorcontrol of drop 572,220 position Poor control of drop volumeThermoelastic An actuator which Low power consumption Efficient aqueousIJ03, IJ09, IJ17, IJ18 bend actuator relies upon Many ink types can beused operation requires IJ19, IJ20, IJ21, IJ22 differential thermalSimple planar fabrication a thermal insulator IJ23, IJ24, IJ27, IJ28expansion upon Small chip area required for on the hot side IJ29, IJ30,IJ31, IJ32 Joule heating is used. each actuator Corrosion preventionIJ33, IJ34, IJ35, IJ36 Fast operation can be difficult IJ37, IJ38, IJ39,IJ40 High efficiency Pigmented inks may IJ41 CMOS compatible voltagesand be infeasible, as currents pigment particles Standard MEMS processescan may jam the bend be used actuator Easy extension from single nozzlesto pagewidth print heads High CTE A material with a very High force canbe generated Requires special IJ09, IJ17, IJ18, IJ20 thermoelastic highcoefficient of PTFE is a candidate for low material (e.g. PTFE) IJ21,IJ22, IJ23, IJ24 actuator thermal expansion (CTE) dielectric constantinsulation Requires a PTFE IJ27, IJ28, IJ29, IJ30 such as in ULSIdeposition process, IJ31, IJ42, IJ43, IJ44 polytetrafluoroethylene Verylow power consumption which is not yet (PTFE) is used. Many ink typescan be used standard in ULSI fabs As high CTE materials Simple planarfabrication PTFE deposition are usually non- Small chip area requiredfor cannot be followed conductive, a heater each actuator with hightemperature fabricated from a Fast operation (above 350 °C.) conductivematerial High efficiency processing is incorporated. A 50 CMOScompatible voltages and Pigmented inks may μm long PTFE bend currents beinfeasible, as actuator with Easy extension from single pigmentparticles polysilicon heater nozzles to pagewidth print may jam the bendand 15 mW power heads actuator input can provide 180 μN force and 10 μmdeflection. Actuator motions include: Bend Push Buckle Rotate ConductiveA polymer with a High force can be generated Requires special IJ24polymer high coefficient of Very low power consumption materialsdevelopment thermoelastic thermal expansion Many ink types can be used(High CTE conductive actuator (such as PTFE) is Simple planarfabrication polymer) doped with conducting Small chip area required forRequires a PTFE substances to each actuator deposition process, increaseits Fast operation which is not yet conductivity to about Highefficiency standard in ULSI fabs 3 orders of magnitude CMOS compatiblevoltages and PTFE deposition cannot below that of currents be followedwith high copper. The conducting Easy extension from single temperature(above polymer expands nozzles to pagewidth print 350 °C.) processingwhen resistively heated. heads Evaporation and CVD Examples ofconducting deposition techniques dopants include: cannot be used Carbonnanotubes Pigmented inks may Metal fibers be infeasible, as Conductivepolymers pigment particles such as doped may jam the bend polythiopheneactuator Carbon granules Shape memory A shape memory alloy High force isavailable (stresses Fatigue limits IJ26 alloy such as TiNi (also ofhundreds of MPa) maximum number of known as Nitinol - Large strain isavailable (more cycles Nickel Titanium alloy than 3%) Low strain (1%) isdeveloped at the High corrosion resistance required to extend NavalOrdnance Simple construction fatigue resistance Laboratory) is Easyextension from single Cycle rate limited thermally switched nozzles topagewidth print by heat removal between its weak heads Requires unusualmartensitic state and Low voltage operation materials (TiNi) its highstiffness The latent heat of austenic state. The transformation mustshape of the actuator be provided in its martensitic High currentoperation state is deformed Requires pre-stressing relative to the todistort the austenic shape. martensitic state The shape change causesejection of a drop. Linear Magnetic Linear magnetic Linear Magneticactuators can Requires unusual semi- IJ12 Actuator actuators include thebe constructed with high conductor materials Linear Induction thrust,long travel, and high such as soft magnetic Actuator (LIA), Linearefficiency using planar alloys (e.g. CoNiFe Permanent Magnetsemiconductor fabrication [1]) Synchronous Actuator techniques Somevarieties also (LPMSA), Linear Long actuator travel is available requirepermanent Reluctance Synchronous Medium force is available magneticmaterials Actuator (LRSA), Linear Low voltage operation such asNeodymium Switched Reluctance iron boron (NdFeB) Actuator (LSRA),Requires complex and the Linear Stepper multi-phase drive Actuator(LSA). circuitry High current operation

BASIC OPERATION MODE Operational mode Description AdvantagesDisadvantages Examples Actuator directly This is the simplest Simpleoperation Drop repetition rate is usually limited to less Thermal inkjetpushes ink mode of operation: No external fields required than 10 KHz.However, this is not Piezoelectric inkjet the actuator directlySatellite drops can be avoided if fundamental to the method, but isrelated IJ01, IJ02, IJ03, IJ04 supplies sufficient drop velocity is lessthan 4 to the refill method normally used IJ05, IJ06, IJ07, IJ09 kineticenergy to m/s All of the drop kinetic energy must be IJ11, IJ12, IJ14,IJ16 expel the drop. The Can be efficient, depending provided by theactuator IJ20, IJ22, IJ23, IJ24 drop must have a upon the actuator usedSatellite drops usually form if drop velocity IJ25, IJ26, IJ27, IJ28sufficient velocity is greater than 4.5 m/s IJ29, IJ30, IJ31, IJ32 toovercome the IJ33, IJ34, IJ35, IJ36 surface tension. IJ37, IJ38, IJ39,IJ40 IJ41, IJ42, IJ43, IJ44 Proximity The drops to be Very simple printhead Requires close proximity between the print Silverbrook, EP 0771printed are selected fabrication can be used head and the print media ortransfer roller 658 A2 and related by some manner (e.g. The dropselection means does May require two print heads printing patentapplications thermally induced not need to provide the alternate rows ofthe image surface tension energy required to separate Monolithic colorprint heads are difficult reduction of pressur- the drop from the nozzleized ink). Selected drops are separated from the ink in the nozzle bycontact with the print medium or a transfer roller. Electrostatic pullThe drops to be printed Very simple print head Requires very highelectrostatic field Silverbrook, EP 0771 on ink are selected byfabrication can be used Electrostatic field for small nozzle sizes is658 A2 and related some manner (e.g. The drop selection means does aboveair breakdown patent applications thermally induced not need to providethe Electrostatic field may attract dust Tone-Jet surface tension energyrequired to separate reduction of pressur- the drop from the nozzle izedink). Selected drops are separated from the ink in the nozzle by astrong electric field. Magnetic pull on The drops to be Very simpleprint head Requires magnetic ink Silverbrook, EP 0771 ink printed areselected fabrication can be used Ink colors other than black aredifficult 658 A2 and related by some manner (e.g. The drop selectionmeans does Requires very high magnetic fields patent applicationsthermally induced not need to provide the surface tension energyrequired to separate reduction of pressur- the drop from the nozzle izedink). Selected drops are separated from the ink in the nozzle by astrong magnetic field acting on the magnetic ink. Shutter The actuatormoves a High speed (>50 KHz) Moving parts are required IJ13, IJ17, IJ21shutter to block ink operation can be achieved Requires ink pressuremodulator flow to the nozzle. due to reduced refill time Friction andwear must be considered The ink pressure is Drop timing can be veryStiction is possible pulsed at a multiple accurate of the drop ejectionThe actuator energy can be frequency. very low Shuttered grill Theactuator moves a Actuators with small travel can Moving parts arerequired IJ08, IJ15, IJ18, IJ19 shutter to block ink be used Requiresink pressure modulator flow through a grill Actuators with small forcecan Friction and wear must be considered to the nozzle. The be usedStiction is possible shutter movement need High speed (>50 KHz) only beequal to operation can be achieved the width of the grill holes. Pulsedmagnetic A pulsed magnetic Extremely low energy operation Requires anexternal pulsed magnetic field IJ10 pull on ink pusher field attracts an‘ink is possible Requires special materials for both the pusher’ at thedrop No heat dissipation problems actuator and the ink pusher ejectionfrequency. Complex construction An actuator controls a catch, whichprevents the ink pusher from moving when a drop is not to be ejected.

AUXILIARY MECHANISM (APPLIED TO ALL NOZZLES) Auxiliary MechanismDescription Advantages Disadvantages Examples None The actuator directlySimplicity of construction Drop ejection energy must be supplied Mostinkjets, including fires the ink drop, Simplicity of operation byindividual nozzle actuator piezoelectric and and there is no Smallphysical size thermal bubble. external field or other IJ01-IJ07, IJ09,IJ11 mechanism required. IJ12, IJ14, IJ20, IJ22 IJ23-IJ45 Oscillatingink The ink pressure Oscillating ink pressure can Requires external inkpressure oscillator Silverbrook, EP 0771 pressure oscillates, providingprovide a refill pulse, Ink pressure phase and amplitude must 658 A2 andrelated (including much of the drop allowing higher operating becarefully controlled patent applications acoustic ejection energy. Thespeed Acoustic reflections in the ink chamber IJ08, IJ13, IJ15, IJ17stimulation) actuator selects The actuators may operate with must bedesigned for IJ18, IJ19, IJ21 which drops are to be much lower energyfired by selectively Acoustic lenses can be used to blocking or enablingfocus the sound on the nozzles. The ink nozzles pressure oscillation maybe achieved by vibrating the print head, or preferably by an actuator inthe ink supply. Media proximity The print head is Low power Precisionassembly required Silverbrook, EP 0771 placed in close High accuracyPaper fibers may cause problems 658 A2 and related proximity to theSimple print head construction Cannot print on rough substrates patentapplications print medium. Selected drops protrude from the print headfurther than unselected drops, and contact the print medium. The dropsoaks into the medium fast enough to cause drop separation. Transferroller Drops are printed to High accuracy Bulky Silverbrook, EP 0771 atransfer roller Wide range of print substrates Expensive 658 A2 andrelated instead of straight can be used Complex construction patentapplications to the print medium. Ink can be dried on the transferTektronix hot melt A transfer roller roller piezoelectric inkjet canalso be used for Any of the IJ series proximity drop separation.Electrostatic An electric field is Low power Field strength required forseparation Silverbrook, EP 0771 used to accelerate Simple print headconstruction of small drops is near or above air 658 A2 and relatedselected drops towards breakdown patent applications the print medium.Tone-Jet Direct magnetic A magnetic field is Low power Requires magneticink Silverbrook, EP 0771 field used to accelerate Simple print headconstruction Requires strong magnetic field 658 A2 and related selecteddrops of patent applications magnetic ink towards the print medium.Cross magnetic The print head is Does not require magnetic Requiresexternal magnet IJ06, IJ16 field placed in a constant materials to beintegrated in Current densities may be high, resulting magnetic field.The the print head manufacturing in electromigration problems Lorenzforce in a process current carrying wire is used to move the actuator.Pulsed magnetic A pulsed magnetic Very low power operation is Complexprint head construction IJ10 field field is used to possible Magneticmaterials required in print head cyclically attract a Small print headsize paddle, which pushes on the ink. A small actuator moves a catch,which selectively prevents the paddle from moving.

ACTUATOR AMPLIFICATION OR MODIFICATION METHOD Actuator amplificationDescription Advantages Disadvantages Examples None No actuatormechanical Operational simplicity Many actuator mechanisms have insuf-Thermal Bubble InkJet amplification is ficient travel, or insufficientforce, IJ01, IJ02, IJ06, IJ07 used. The actuator to efficiently drivethe drop ejection IJ16, IJ25, IJ26 directly drives the process dropejection process. Differential An actuator material Provides greatertravel in a High stresses are involved Piezoelectric expansion bendexpands more on reduced print head area Care must be taken that thematerials IJ03, IJ09, IJ17-IJ24 actuator one side than on The bendactuator converts a do not delaminate IJ27 IJ29-IJ39, IJ42, the other.The high force low travel actuator Residual bend resulting from highIJ43, IJ44 expansion may be mechanism to high travel, temperature orhigh stress during thermal, piezoelectric, lower force mechanism.formation magnetostrictive, or other mechanism. Transient bend Atrilayer bend Very good temperature stability High stresses are involvedIJ40, IJ41 actuator actuator where the two High speed, as a new drop canCare must be taken that the materials outside layers are be fired beforeheat dissipates do not delaminate identical. This cancels Cancelsresidual stress of bend due to ambient formation temperature andresidual stress. The actuator only responds to transient heating of oneside or the other. Actuator stack A series of thin Increased travelIncreased fabrication complexity Some piezoelectric ink actuators arestacked. Reduced drive voltage Increased possibility of short circuitsjets This can be due to pinholes IJ04 appropriate where actuatorsrequire high electric field strength, such as electrostatic andpiezoelectric actuators. Multiple actuators Multiple smaller Increasesthe force available Actuator forces may not add linearly, IJ12, IJ13,IJ18, IJ20 actuators are used from an actuator reducing efficiency IJ22,IJ28, IJ42, IJ43 simultaneously to Multiple actuators can be move theink. Each positioned to control ink flow actuator need accuratelyprovide only a portion of the force required. Linear Spring A linearspring is Matches low travel actuator Requires print head area for thespring IJ15 used to transform a with higher travel motion with smallrequirements travel and high force Non-contact method of motion into alonger travel, transformation lower force motion. Reverse spring Theactuator loads a Better coupling to the ink Fabrication complexity IJ05,IJ11 spring. When the High stress in the spring actuator is turned off,the spring releases. This can reverse the force/distance curve of theactuator to make it compatible with the force/time requirements of thedrop ejection. Coiled actuator A bend actuator is Increases travelGenerally restricted to planar IJ17, IJ21, IJ34, IJ35 coiled to provideReduces chip area implementations due to extreme greater travel in aPlanar implementations are fabrication difficulty in other reduced chiparea. relatively easy to fabricate. orientations. Flexure bend A bendactuator has Simple means of increasing Care must be taken not to exceedthe IJ10, IJ19, IJ33 actuator a small region near travel of a bendactuator elastic limit in the flexure area the fixture point, Stressdistribution is very uneven which flexes much Difficult to accuratelymodel with finite more readily than element analysis the remainder ofthe actuator. The actuator flexing is effectively converted from an evencoiling to an angular bend, resulting in greater travel of the actuatortip. Gears Gears can be used to Low force, low travel actuators Movingparts are required IJ13 increase travel at can be used Several actuatorcycles are required the expense of Can be fabricated using More complexdrive electronics duration. Circular standard surface MEMS Complexconstruction gears, rack and pinion, processes Friction, friction, andwear are possible ratchets, and other gearing methods can be used. CatchThe actuator controls Very low actuator energy Complex construction IJ10a small catch. The Very small actuator size Requires external forcecatch either enables Unsuitable for pigmented inks or disables movementof an ink pusher that is controlled in a bulk manner. Buckle plate Abuckle plate can be Very fast movement achievable Must stay withinelastic limits of the S. Hirata et al, “An Ink- used to change amaterials for long device life jet Head . . . ”, Proc. slow actuatorinto a High stresses involved IEEE MEMS, February fast motion. It canGenerally high power requirement 1996, pp 418-423. also convert a highIJ18, IJ27 force, low travel actuator into a high travel, medium forcemotion. Tapered magnetic A tapered magnetic Linearizes the magneticComplex construction IJ14 pole pole can increase force/distance curvetravel at the expense of force. Lever A lever and fulcrum Matches lowtravel actuator High stress around the fulcrum IJ32, IJ36, IJ37 is usedto transform with higher travel a motion with small requirements traveland high force Fulcrum area has no linear into a motion with movement,and can be used longer travel and for a fluid seal lower force. Thelever can also reverse the direction of travel. Rotary impeller Theactuator is High mechanical advantage Complex construction IJ28connected to a rotary The ratio of force to travel of Unsuitable forpigmented inks impeller. A small the actuator can be matched angulardeflection of to the nozzle requirements by the actuator results varyingthe number of in a rotation of the impeller vanes impeller vanes, whichpush the ink against stationary vanes and out of the nozzle. Acousticlens A refractive or No moving parts Large area required 1993 Hadimiogluet al, diffractive (e.g. zone Only relevant for acoustic ink jets EUP550,192 plate) acoustic lens 1993 Elrod et al, EUP is used toconcentrate 572,220 sound waves. Sharp conductive A sharp point is usedSimple construction Difficult to fabricate using standard Tone-jet pointto concentrate an VLSI processes for a surface ejecting electrostaticfield. ink-jet Only relevant for electrostatic ink jets

ACTUATOR MOTION Actuator motion Description Advantages DisadvantagesExamples Volume The volume of the Simple construction High energy istypically required to Hewlett-Packard expansion actuator changes, in thecase achieve volume expansion. This leads to Thermal InkJet pushing theink in of thermal ink jet thermal stress, cavitation, and kogation CanonBubblejet all directions. in thermal ink jet implementations Linear, Theactuator moves in Efficient coupling High fabrication complexity may beIJ01, IJ02, IJ04, IJ07 normal to a direction normal to ink dropsrequired to achieve perpendicular motion IJ11, IJ14 chip surface to theprint head ejected normal to surface. The nozzle the surface istypically in the line of movement. Linear, The actuator moves Suitablefor planar Fabrication complexity IJ12, IJ13, IJ15, IJ33, parallel toparallel to the print fabrication Friction IJ34, IJ35, IJ36 chip surfacehead surface. Drop Stiction ejection may still be normal to the surface.Membrane push An actuator with a The effective Fabrication complexity1982 Howkins U.S. Pat. No. high force but small area of the Actuatorsize 4,459,601 area is used to push actuator becomes Difficulty ofintegration in a VLSI a stiff membrane that the membrane area process isin contact with the ink. Rotary The actuator causes Rotary levers mayDevice complexity IJ05, IJ08, IJ13, IJ28 the rotation of some be used toMay have friction at a pivot point element, such a grill increase travelor impeller Small chip area requirements Bend The actuator bends A verysmall Requires the actuator to be made from 1970 Kyser et al U.S. Pat.No. when energized. This change in at least two distinct layers, or to3,946,398 may be due to dimensions can have a thermal difference acrossthe 1973 Stemme U.S. Pat. No. differential thermal be converted actuator3,747,120 expansion, piezo- to a large IJ03, IJ09, IJ10, IJ19 electricexpansion, motion. IJ23, IJ24, IJ25, IJ29 magnetostriction, IJ30, IJ31,IJ33, IJ34 or other form of IJ35 relative dimensional change. Swivel Theactuator swivels Allows operation Inefficient coupling to the ink motionIJ06 around a central where the net pivot. This motion is linear forceon suitable where there the paddle is are opposite forces zero appliedto opposite Small chip area sides of the paddle, requirements e.g.Lorenz force. Straighten The actuator is Can be used Requires carefulbalance of stresses to IJ26, IJ32 normally bent, and with shape ensurethat the quiescent bend is straightens when memory alloys accurateenergized. where the austenic phase is planar Double bend The actuatorbends in One actuator can Difficult to make the drops ejected by IJ36,IJ37, IJ38 one direction when one be used to power both bend directionsidentical. element is energized, two nozzles. A small efficiency losscompared to and bends the other way Reduced chip size. equivalent singlebend actuators. when another element is Not sensitive to energized.ambient temperature Shear Energizing the actuator Can increase the Notreadily applicable to other actuator 1985 Fishbeck U.S. Pat. No. causesa shear motion in effective travel mechanisms 4,584,590 the actuatormaterial. of piezoelectric actuators Radial The actuator squeezesRelatively easy High force required 1970 Zoltan U.S. Pat. No.constriction an ink reservoir, to fabricate Inefficient 3,683,212forcing ink from a single nozzles Difficult to integrate with VLSIconstricted nozzle. from glass processes tubing as macroscopicstructures Coil/uncoil A coiled actuator Easy to fabricate Difficult tofabricate for non-planar IJ17, IJ21, IJ34, IJ35 uncoils or coils more asa planar devices tightly. The motion of VLSI process Poor out-of-planestiffness the free end of the Small area actuator ejects the ink.required, therefore low cost Bow The actuator bows (or Can increase theMaximum travel is constrained IJ16, IJ18, IJ27 buckles) in the speed oftravel High force required middle when energized. Mechanically rigidPush-Pull Two actuators control The structure is Not readily suitablefor inkjets which IJ18 a shutter. One pinned at both directly push theink actuator pulls the ends, so has a shutter, and the other highout-of- pushes it. plane rigidity Curl inwards A set of actuators curlGood fluid flow Design complexity IJ20, IJ42 inwards to reduce to theregion the volume of ink that behind the they enclose. actuatorincreases efficiency Curl outwards A set of actuators Relatively simpleRelatively large chip area IJ43 curl outwards, construction pressurizingink in a chamber surrounding the actuators, and expelling ink from anozzle in the chamber. Iris Multiple vanes enclose High efficiency Highfabrication complexity IJ22 a volume of ink. These Small chip area Notsuitable for pigmented inks simultaneously rotate, reducing the volumebetween the vanes. Acoustic vibration The actuator vibrates The actuatorcan Large area required for efficient 1993 Hadimioglu et al, at a highfrequency. be physically operation at useful frequencies EUP 550,192distant from the Acoustic coupling and crosstalk 1993 Elrod et al, EUPink Complex drive circuitry 572,220 Poor control of drop volume andposition None In various ink jet No moving parts Various other tradeoffsare required Silverbrook, EP 0771 designs the actuator to eliminatemoving parts 658 A2 and related does not move. patent applicationsTone-jet

NOZZLE REFILL METHOD Nozzle refill method Description AdvantagesDisadvantages Examples Surface tension After the actuator Fabricationsimplicity Low speed Thermal inkjet is energized, it Operationalsimplicity Surface tension force relatively small Piezoelectric inkjettypically returns compared to actuator force IJ01-IJ07, IJ10-IJ14rapidly to its normal Long refill time usually dominates the IJ16, IJ20,IJ22-IJ45 position. This rapid total repetition rate return sucks in airthrough the nozzle opening. The ink surface tension at the nozzle thenexerts a small force restoring the meniscus to a minimum area. ShutteredInk to the nozzle High speed Requires common ink pressure oscillatorIJ08, IJ13, IJ15, IJ17 oscillating ink chamber is provided Low actuatorenergy, as the May not be suitable for pigmented inks IJ18, IJ19, IJ21pressure at a pressure that actuator need only open or oscillates attwice close the shutter, instead of the drop ejection ejecting the inkdrop frequency. When a drop is to be ejected, the shutter is opened for3 half cycles: drop ejection, actuator return, and refill. Refillactuator After the main actuator High speed, as the nozzle is Requirestwo independent actuators per IJ09 has ejected a drop a activelyrefilled nozzle second (refill) actuator is energized. The refillactuator pushes ink into the nozzle chamber. The refill actuator returnsslowly, to prevent its return from emptying the chamber again. Positiveink The ink is held a slight High refill rate, therefore a Surface spillmust be prevented Silverbrook, EP 0771 pressure positive pressure. Afterhigh drop repetition rate is Highly hydrophobic print head surfaces 658A2 and related the ink drop is ejected, possible are required patentapplications the nozzle chamber fills Alternative for: quickly assurface IJ01-IJ07, IJ10-IJ14 tension and ink pressure IJ16, IJ20,IJ22-IJ45 both operate to refill the nozzle.

METHOD OF RESTRICTING BACK-FLOW THROUGH INLET Inlet back-flowrestriction method Description Advantages Disadvantages Examples Longinlet The ink inlet channel Design simplicity Restricts refill rateThermal inkjet channel to the nozzle chamber Operational simplicity Mayresult in a relatively large chip Piezoelectric inkjet is made long andReduces crosstalk area IJ42, IJ43 relatively narrow, Only partiallyeffective relying on viscous drag to reduce inlet back-flow. Positiveink The ink is under a Drop selection and separation Requires a method(such as a nozzle rim Silverbrook, EP 0771 pressure positive pressure,forces can be reduced or effective hydrophobizing, or both) to 658 A2and related so that in the Fast refill time prevent flooding of theejection surface patent applications quiescent state some of the printhead. Possible operation of the of the ink drop already following:protrudes from the IJ01-IJ07, IJ09-IJ12 nozzle. This reduces IJ14, IJ16,IJ20, IJ22, the pressure in the IJ23-IJ34, IJ36-IJ41 nozzle chamberwhich IJ44 is required to eject a certain volume of ink. The reductionin chamber pressure results in a reduction in ink pushed out through theinlet. Baffle One or more baffles The refill rate is not as Designcomplexity HP Thermal Ink Jet are placed in the restricted as the longMay increase fabrication complexity Tektronix piezoelectric inlet inkflow. When inlet method. (e.g. Tektronix hot melt Piezoelectric inkjetthe actuator is Reduces crosstalk print heads). energized, the rapid inkmovement creates eddies which restrict the flow through the inlet. Theslower refill process is unre- stricted, and does not result in eddies.Flexible flap In this method Significantly reduces back-flow Notapplicable to most inkjet config- Canon restricts inlet recentlydisclosed by for edge-shooter thermal ink urations Canon, the expandingjet devices Increased fabrication complexity actuator (bubble) Inelasticdeformation of polymer flap pushes on a flexible results in creep overextended use flap that restricts the inlet. Inlet filter A filter islocated Additional advantage of ink Restricts refill rate IJ04, IJ12,IJ24, IJ27 between the ink inlet filtration May result in complexconstruction IJ29, IJ30 and the nozzle chamber. Ink filter may befabricated The filter has a with no additional process multitude ofsmall steps holes or slots, restricting ink flow. The filter alsoremoves particles which may block the nozzle. Small inlet The ink inletchannel Design simplicity Restricts refill rate IJ02, IJ37, IJ44compared to to the nozzle chamber May result in a relatively large chipnozzle has a substantially area smaller cross section Only partiallyeffective than that of the nozzle, resulting in easier ink egress out ofthe nozzle than out of the inlet. Inlet shutter A secondary actuatorIncreases speed of the ink- Requires separate refill actuator and IJ09controls the position jet print head operation drive circuit of ashutter, closing off the ink inlet when the main actuator is energized.The inlet is The method avoids Back-flow problem is Requires carefuldesign to minimize the IJ01, IJ03, IJ05, IJ06 located behind the problemof inlet eliminated negative pressure behind the paddle IJ07, IJ10,IJ11, IJ14 the ink-pushing back-flow by arrang- IJ16, IJ22, IJ23, IJ25surface ing the ink-pushing IJ28, IJ31, IJ32, IJ33 surface of the IJ34,IJ35, IJ36, IJ39 actuator between the IJ40, IJ41 inlet and the nozzle.Part of the The actuator and a Significant reductions in back- Smallincrease in fabrication complexity IJ07, IJ20, IJ26, IJ38 actuator moveswall of the ink flow can be achieved to shut off chamber are arrangedCompact designs possible the inlet so that the motion of the actuatorcloses off the inlet. Nozzle actuator In some configura- Ink back-flowproblem is None related to ink back-flow on Silverbrook, EP 0771 doesnot result tions of ink jet, eliminated actuation 658 A2 and related inink back-flow there is no expan- patent applications sion or movement ofValve-jet an actuator which may Tone-jet cause ink back-flow IJ08, IJ13,IJ15, IJ17 through the inlet. IJ18, IJ19, IJ21

NOZZLE CLEARING METHOD Nozzle Clearing method Description AdvantagesDisadvantages Examples Normal nozzle All of the nozzles are No addedcomplexity on the May not be sufficient to displace dried Most ink jetsystems firing fired periodically, print head ink IJ01-IJ07, IJ09-IJ12before the ink has a IJ14, IJ16, IJ20, IJ22 chance to dry. WhenIJ23-IJ34, IJ36-IJ45 not in use the nozzles are sealed (capped) againstair. The nozzle firing is usually performed during a special clear- ingcycle, after first moving the print head to a cleaning station. Extrapower to In systems which heat Can be highly effective if the Requireshigher drive voltage for Silverbrook, EP 0771 ink heater the ink, but donot heater is adjacent to the clearing 658 A2 and related boil it undernormal nozzle May require larger drive transistors patent applicationssituations, nozzle clearing can be achieved by over- powering the heaterand boiling ink at the nozzle. Rapid succession The actuator is firedDoes not require extra drive Effectiveness depends substantially May beused with: of actuator pulses in rapid succession. circuits on the printhead upon the configuration of the inkjet IJ01-IJ07, IJ09-IJ11 In someconfigurations, Can be readily controlled and nozzle IJ14, IJ16, IJ20,IJ22 this may cause heat initiated by digital logic IJ23-IJ25, IJ27-IJ34build-up at the nozzle IJ36-IJ45 which boils the ink, clearing thenozzle. In other situations, it may cause sufficient vibrations todislodge clogged nozzles. Extra power to Where an actuator is A simplesolution where Not suitable where there is a hard limit May be usedwith: ink pushing not normally driven applicable to actuator movementIJ03, IJ09, IJ16, IJ20 actuator to the limit of its IJ23, IJ24, IJ25,IJ27 motion, nozzle clearing IJ29, IJ30, IJ31, IJ32 may be assisted byIJ39, IJ40, IJ41, IJ42 providing an enhanced IJ43, IJ44, IJ45 drivesignal to the actuator. Acoustic An ultrasonic wave is A high nozzleclearing High implementation cost if system does IJ08, IJ13, IJ15, IJ17resonance applied to the ink capability can be achieved not alreadyinclude an acoustic actuator IJ18, IJ19, IJ21 chamber. This wave is Maybe implemented at very of an appropriate low cost in systems whichamplitude and fre- already include acoustic quency to cause actuatorssufficient force at the nozzle to clear blockages. This is easiest toachieve if the ultrasonic wave is at a resonant frequency of the inkcavity. Nozzle clearing A microfabricated plate Can clear severelyclogged Accurate mechanical alignment is re- Silverbrook, EP 0771 plateis pushed against the nozzles quired 658 A2 and related nozzles. Theplate has Moving parts are required patent applications a post for everynozzle. There is risk of damage to the nozzles The array of postsAccurate fabrication is required Ink pressure pulse The pressure of theMay be effective where other Requires pressure pump or other May be usedwith all IJ ink is temporarily methods cannot be used pressure actuatorseries ink jets increased so that ink Expensive streams from all ofWasteful of ink the nozzles. This may be used in con- junction withactuator energizing. Print head wiper A flexible ‘blade’ Effective forplanar print head Difficult to use if print head surface is Many ink jetsystems is wiped across the surfaces non-planar or very fragile printhead surface. Low cost Requires mechanical parts The blade is usuallyBlade can wear out in high volume print fabricated from a systemsflexible polymer, e.g. rubber or synthetic elastomer. Separate ink Aseparate heater is Can be effective where other Fabrication complexityCan be used with many boiling heater provided at the nozzle clearingmethods IJ series ink jets nozzle although the cannot be used normaldrop e-ection Can be implemented at no mechanism does not additionalcost in some inkjet require it. The configurations heaters do notrequire individual drive circuits, as many nozzles can be clearedsimultaneously, and no imaging is required.

NOZZLE PLATE CONSTRUCTION Nozzle plate construction DescriptionAdvantages Disadvantages Examples Electroformed A nozzle plate isFabrication simplicity High temperatures and pressures are HewlettPackard nickel separately fabricated required to bond nozzle plateThermal Inkjet from electroformed Minimum thickness constraints nickel,and bonded Differential thermal expansion to the print head chip. Laserablated or Individual nozzle holes No masks required Each hole must beindividually formed Canon Bubblejet drilled polymer are ablated by anCan be quite fast Special equipment required 1988 Sercel et al., intenseUV laser in a Some control over nozzle Slow where there are manythousands SPIE, Vol. 998 Excimer nozzle plate, which profile is possibleof nozzles per print head Beam Applications, is typically a polymerEquipment required is May produce thin burrs at exit holes pp. 76-83such as polyimide or relatively low cost 1993 Watanabe et al.,polysulphone U.S. Pat. No. 5,208,604 Silicon micro- A separate nozzleHigh accuracy is attainable Two part construction K. Bean, IEEE machinedplate is micromachined High cost Transactions on from single crystalRequires precision alignment Electron Devices, Vol. silicon, and bondedNozzles may be clogged by adhesive ED-25, No. 10, 1978, to the printhead pp 1185-1195 wafer. Xerox 1990 Hawkins et al., U.S. Pat. No.4,899,181 Glass Fine glass capillaries No expensive equipment Very smallnozzle sizes are difficult to 1970 Zoltan U.S. capillaries are drawnfrom glass required form Pat. No. 3,683,212 tubing. This method Simpleto make single nozzles Not suited for mass production has been used formaking individual nozzles, but is difficult to use for bulkmanufacturing of print heads with thousands of nozzles. Monolithic, Thenozzle plate is High accuracy (<1 μm) Requires sacrificial layer underthe Silverbrook, EP 0771 surface micro- deposited as a layer Monolithicnozzle plate to form the nozzle chamber 658 A2 and related machinedusing using standard VLSI Low cost Surface may be fragile to the touchpatent applications VLSI litho- deposition techniques. Existingprocesses can be IJ01, IJ02, IJ04, IJ11 graphic Nozzles are etched inused IJ12, IJ17, IJ18, IJ20 processes the nozzle plate using IJ22, IJ24,IJ27, IJ28 VLSI lithography and IJ29, IJ30, IJ31, IJ32 etching. IJ33,IJ34, IJ36, IJ37 IJ38, IJ39, IJ40, IJ41 IJ42, IJ43, IJ44 Monolithic, Thenozzle plate is a High accuracy (<1 μm) Requires long etch times IJ03,IJ05, IJ06, IJ07 etched through buried etch stop in Monolithic Requiresa support wafer IJ08, IJ09, IJ10, IJ13 substrate the wafer. Nozzle Lowcost IJ14, IJ15, IJ16, IJ19 chambers are etched in No differentialexpansion IJ21, IJ23, IJ25, IJ26 the front of the wafer, and the waferis thinned from the back side. Nozzles are then etched in the etch stoplayer. No nozzle plate Various methods have No nozzles to become cloggedDifficult to control drop position accu- Ricoh 1995 Sekiya et al beentried to eliminate rately U.S. Pat. No. 5,412,413 the nozzles entirely,Crosstalk problems 1993 Hadimioglu et al to prevent nozzle EUP 550,192clogging. These include 1993 Elrod et al EUP thermal bubble mecha-572,220 nisms and acoustic lens mechanisms Trough Each drop ejector hasReduced manufacturing Drop firing direction is sensitive to IJ35 atrough through complexity wicking. which a paddle moves. MonolithicThere is no nozzle plate. Nozzle slit The elimination of No nozzles tobecome clogged Difficult to control drop position accu- 1989 Saito et alinstead of nozzle holes and rately U.S. Pat. No. individual replacementby a Crosstalk problems 4,799,068 nozzles slit encompassing manyactuator posi- tions reduces nozzle clogging, but in- creases crosstalkdue to ink surface waves

DROP EJECTION DIRECTION Ejection direction Description AdvantagesDisadvantages Examples Edge Ink flow is along the Simple constructionNozzles limited to edge Canon Bubblejet 1979 (‘edge shooter’) surface ofthe chip, No silicon etching required High resolution is difficult Endoet al GB patent and ink drops are Good heat sinking via sub- Fast colorprinting requires one print 2,007,162 ejected from the chip strate headper color Xerox heater-in-pit 1990 edge. Mechanically strong Hawkins etal U.S. Ease of chip handing Pat. No. 4,899,181 Tone-jet Surface Inkflow is along the No bulk silicon etching Maximum ink flow is severelyrestricted Hewlett-Packard TIJ (‘roof shooter’) surface of the chip,required 1982 Vaught et al and ink drops are Silicon can make aneffective U.S. Pat. No. ejected from the chip heat sink 4,490,728surface, normal to Mechanical strength IJ02, IJ11, IJ12, IJ20 the planeof the chip. IJ22 Through chip, Ink flow is through High ink flowRequires bulk silicon etching Silverbrook, EP 0771 forward the chip, andink Suitable for pagewidth print 658 A2 and related (‘up shooter’) dropsare ejected High nozzle packing density patent applications from thefront sur- therefore low manufacturing IJ04, IJ17, IJ18, IJ24 face ofthe chip. cost IJ27-IJ45 Through chip, Ink flow is through High ink flowRequires wafer thinning IJ01, IJ03, IJ05, IJ06 reverse the chip, and inkSuitable for pagewidth print Requires special handling during IJ07,IJ08, IJ09, IJ10 (‘down shooter’) drops are ejected High nozzle packingdensity manufacture IJ13, IJ14, IJ15, IJ16 from the rear surfacetherefore low manufacturing IJ19, IJ21, IJ23, IJ25 of the chip. costIJ26 Through actuator Ink flow is through Suitable for piezoelectricPagewidth print heads require several Epson Stylus the actuator, whichprint heads thousand connections to drive circuits Tektronix hot melt isnot fabricated as Cannot be manufactured in standard piezoelectric inkjets part of the same CMOS fabs substrate as the Complex assemblyrequired drive transistors.

INK TYPE Ink type Description Advantages Disadvantages Examples Aqueous,dye Water based ink Environmentally friendly Slow drying Most existinginkjets which typically No odor Corrosive All IJ series ink jetscontains: water, Bleeds on paper Silverbrook, EP 0771 dye, surfactant,May strikethrough 658 A2 and related humectant, and Cockles paper patentapplications biocide. Modern ink dyes have high water- fastness, lightfastness Aqueous, pigment Water based ink Environmentally friendly Slowdrying IJ02, IJ04, IJ21, IJ26 which typically No odor Corrosive IJ27,IJ30 contains: water, Reduced bleed Pigment may clog nozzlesSilverbrook, EP 0771 pigment, surfactant, Reduced wicking Pigment mayclog actuator mechanisms 658 A2 and related humectant, and Reducedstrikethrough Cockles paper patent applications biocide. Piezoelectricink-jets Pigments have an Thermal ink jets (with advantage in reducedsignificant bleed, wicking restrictions) and strikethrough. Methyl EthylMEK is a highly vola- Very fast drying Odorous All IJ series ink jetsKetone (MEK) tile solvent used for Prints on various substratesFlammable industrial printing such as metals and plastics on difficultsurfaces such as aluminum cans. Alcohol Alcohol based inks Fast dryingSlight odor All IJ series ink jets (ethanol, 2- can be used whereOperates at sub-freezing Flammable butanol, and the printer musttemperatures others) operate at tempera- Reduced paper cockle turesbelow the Low cost freezing point of water. An example of this isin-camera consumer photographic printing. Phase change The ink is solidat No drying time - ink instantly High viscosity Tektronix hot melt (hotmelt) room temperature, and freezes on the print medium Printed inktypically has a ‘waxy’ feel piezoelectric ink jets is melted in theAlmost any print medium can Printed pages may ‘block’ 1989 Nowak U.S.Pat. print head before jet- be used Ink temperature may be above thecurie No. 4,820,346 ting. Hot melt inks No paper cockle occurs point ofpermanent magnets All IJ series ink jets are usually wax based, Nowicking occurs Ink heaters consume power with a melting point No bleedoccurs Long warm-up time around 80° C. After No strikethrough occursjetting the ink freezes almost instantly upon contacting the printmedium or a transfer roller. Oil Oil based inks are High solubilitymedium for High viscosity: this is a significant All IJ series ink jetsextensively used in some dyes limitation for use in inkjets, whichoffset printing. They Does not cockle paper usually require a lowviscosity. Some have advantages in Does not wick through paper shortchain and multi-branched oils improved characteris- have a sufficientlylow viscosity. tics on paper (especi- Slow drying ally no wicking orcockle). Oil soluble dies and pigments are required. Microemulsion Amicroemulsion is a Stops ink bleed Viscosity higher than water All IJseries ink jets stable, self forming High dye solubility Cost isslightly higher than water based emulsion of oil, water, Water, oil, andamphiphilic ink and surfactant. The soluble dies can be used Highsurfactant concentration required characteristic drop Can stabilizepigment (around 5%) size is less than suspensions 100 nm, and is deter-mined by the preferred curvature of the surfactant.Ink Jet Printing

A large number of new forms of ink jet printers have been developed tofacilitate alternative ink jet technologies for the image processing anddata distribution system. Various combinations of ink jet devices can beincluded in printer devices incorporated as part of the presentinvention. Australian Provisional Patent Applications relating to theseink jets which are specifically incorporated by cross reference include:

Australian Provisional Number Filing Date Title PO8066 Jul. 15, 1997Image Creation Method and Apparatus (IJ01) PO8072 Jul. 15, 1997 ImageCreation Method and Apparatus (IJ02) PO8040 Jul. 15, 1997 Image CreationMethod and Apparatus (IJ03) PO8071 Jul. 15, 1997 Image Creation Methodand Apparatus (IJ04) PO8047 Jul. 15, 1997 Image Creation Method andApparatus (IJ05) PO8035 Jul. 15, 1997 Image Creation Method andApparatus (IJ06) PO8044 Jul. 15, 1997 Image Creation Method andApparatus (IJ07) PO8063 Jul. 15, 1997 Image Creation Method andApparatus (IJ08) PO8057 Jul. 15, 1997 Image Creation Method andApparatus (IJ09) PO8056 Jul. 15, 1997 Image Creation Method andApparatus (IJ10) PO8069 Jul. 15, 1997 Image Creation Method andApparatus (IJ11) PO8049 Jul. 15, 1997 Image Creation Method andApparatus (IJ12) PO8036 Jul. 15, 1997 Image Creation Method andApparatus (IJ13) PO8048 Jul. 15, 1997 Image Creation Method andApparatus (IJ14) PO8070 Jul. 15, 1997 Image Creation Method andApparatus (IJ15) PO8067 Jul. 15, 1997 Image Creation Method andApparatus (IJ16) PO8001 Jul. 15, 1997 Image Creation Method andApparatus (IJ17) PO8038 Jul. 15, 1997 Image Creation Method andApparatus (IJ18) PO8033 Jul. 15, 1997 Image Creation Method andApparatus (IJ19) PO8002 Jul. 15, 1997 Image Creation Method andApparatus (IJ20) PO8068 Jul. 15, 1997 Image Creation Method andApparatus (IJ21) PO8062 Jul. 15, 1997 Image Creation Method andApparatus (IJ22) PO8034 Jul. 15, 1997 Image Creation Method andApparatus (IJ23) PO8039 Jul. 15, 1997 Image Creation Method andApparatus (IJ24) PO8041 Jul. 15, 1997 Image Creation Method andApparatus (IJ25) PO8004 Jul. 15, 1997 Image Creation Method andApparatus (IJ26) PO8037 Jul. 15, 1997 Image Creation Method andApparatus (IJ27) PO8043 Jul. 15, 1997 Image Creation Method andApparatus (IJ28) PO8042 Jul. 15, 1997 Image Creation Method andApparatus (IJ29) PO8064 Jul. 15, 1997 Image Creation Method andApparatus (IJ30) PO9389 Sep. 23, 1997 Image Creation Method andApparatus (IJ31) PO9391 Sep. 23, 1997 Image Creation Method andApparatus (IJ32) PP0888 Dec. 22, 1997 Image Creation Method andApparatus (IJ33) PP0891 Dec. 22, 1997 Image Creation Method andApparatus (IJ34) PP0890 Dec. 22, 1997 Image Creation Method andApparatus (IJ35) PP0873 Dec. 22, 1997 Image Creation Method andApparatus (IJ36) PP0993 Dec. 22, 1997 Image Creation Method andApparatus (IJ37) PP0890 Dec. 22, 1997 Image Creation Method andApparatus (IJ38) PP1398 Jan. 19, 1998 An Image Creation Method andApparatus (IJ39) PP2592 Mar. 25, 1998 An Image Creation Method andApparatus (IJ40) PP2593 Mar. 25, 1998 Image Creation Method andApparatus (IJ41) PP3991 Jun. 9, 1998 Image Creation Method and Apparatus(IJ42) PP3987 Jun. 9, 1998 Image Creation Method and Apparatus (IJ43)PP3985 Jun. 9, 1998 Image Creation Method and Apparatus (IJ44) PP3983Jun. 9, 1998 Image Creation Method and Apparatus (IJ45)Ink Jet Manufacturing

Further, the present application may utilize advanced semiconductorfabrication techniques in the construction of large arrays of ink jetprinters. Suitable manufacturing techniques are described in thefollowing Australian provisional patent specifications incorporated hereby cross-reference:

Australian Provisional Number Filing Date Title PO7935 Jul. 15, 1997 AMethod of Manufacture of an Image Creation Apparatus (IJM01) PO7936 Jul.15, 1997 A Method of Manufacture of an Image Creation Apparatus (IJM02)PO7937 Jul. 15, 1997 A Method of Manufacture of an Image CreationApparatus (IJM03) PO8061 Jul. 15, 1997 A Method of Manufacture of anImage Creation Apparatus (IJM04) PO8054 Jul. 15, 1997 A Method ofManufacture of an Image Creation Apparatus (IJM05) PO8065 Jul. 15, 1997A Method of Manufacture of an Image Creation Apparatus (IJM06) PO8055Jul. 15, 1997 A Method of Manufacture of an Image Creation Apparatus(IJM07) PO8053 Jul. 15, 1997 A Method of Manufacture of an ImageCreation Apparatus (IJM08) PO8078 Jul. 15, 1997 A Method of Manufactureof an Image Creation Apparatus (IJM09) PO7933 Jul. 15, 1997 A Method ofManufacture of an Image Creation Apparatus (IJM10) PO7950 Jul. 15, 1997A Method of Manufacture of an Image Creation Apparatus (IJM11) PO7949Jul. 15, 1997 A Method of Manufacture of an Image Creation Apparatus(IJM12) PO8060 Jul. 15, 1997 A Method of Manufacture of an ImageCreation Apparatus (IJM13) PO8059 Jul. 15, 1997 A Method of Manufactureof an Image Creation Apparatus (IJM14) PO8073 Jul. 15, 1997 A Method ofManufacture of an Image Creation Apparatus (IJM15) PO8076 Jul. 15, 1997A Method of Manufacture of an Image Creation Apparatus (IJM16) PO8075Jul. 15, 1997 A Method of Manufacture of an Image Creation Apparatus(IJM17) PO8079 Jul. 15, 1997 A Method of Manufacture of an ImageCreation Apparatus (IJM18) PO8050 Jul. 15, 1997 A Method of Manufactureof an Image Creation Apparatus (IJM19) PO8052 Jul. 15, 1997 A Method ofManufacture of an Image Creation Apparatus (IJM20) PO7948 Jul. 15, 1997A Method of Manufacture of an Image Creation Apparatus (IJM21) PO7951Jul. 15, 1997 A Method of Manufacture of an Image Creation Apparatus(IJM22) PO8074 Jul. 15, 1997 A Method of Manufacture of an ImageCreation Apparatus (IJM23) PO7941 Jul. 15, 1997 A Method of Manufactureof an Image Creation Apparatus (IJM24) PO8077 Jul. 15, 1997 A Method ofManufacture of an Image Creation Apparatus (IJM25) PO8058 Jul. 15, 1997A Method of Manufacture of an Image Creation Apparatus (IJM26) PO8051Jul. 15, 1997 A Method of Manufacture of an Image Creation Apparatus(IJM27) PO8045 Jul. 15, 1997 A Method of Manufacture of an ImageCreation Apparatus (IJM28) PO7952 Jul. 15, 1997 A Method of Manufactureof an Image Creation Apparatus (IJM29) PO8046 Jul. 15, 1997 A Method ofManufacture of an Image Creation Apparatus (IJM30) PO8503 Aug. 11, 1997A Method of Manufacture of an Image Creation Apparatus (IJM30a) PO9390Sep. 23, 1997 A Method of Manufacture of an Image Creation Apparatus(IJM31) PO9392 Sep. 23, 1997 A Method of Manufacture of an ImageCreation Apparatus (IJM32) PP0889 Dec. 22, 1997 A Method of Manufactureof an Image Creation Apparatus (IJM35) PP0887 Dec. 22, 1997 A Method ofManufacture of an Image Creation Apparatus (IJM36) PP0882 Dec. 22, 1997A Method of Manufacture of an Image Creation Apparatus (IJM37) PP0874Dec. 22, 1997 A Method of Manufacture of an Image Creation Apparatus(IJM38) PP1396 Jan. 19, 1998 A Method of Manufacture of an ImageCreation Apparatus (IJM39) PP2591 Mar. 25, 1998 A Method of Manufactureof an Image Creation Apparatus (IJM41) PP3989 Jun. 9, 1998 A Method ofManufacture of an Image Creation Apparatus (IJM40) PP3990 Jun. 9, 1998 AMethod of Manufacture of an Image Creation Apparatus (IJM42) PP3986 Jun.9, 1998 A Method of Manufacture of an Image Creation Apparatus (IJM43)PP3984 Jun. 9, 1998 A Method of Manufacture of an Image CreationApparatus (IJM44) PP3982 Jun. 9, 1998 A Method of Manufacture of anImage Creation Apparatus (IJM45)Fluid Supply

Further, the present application may utilize an ink delivery system tothe ink jet head. Delivery systems relating to the supply of ink to aseries of ink jet nozzles are described in the following Australianprovisional patent specifications, the disclosure of which are herebyincorporated by cross-reference:

Australian Provisional Number Filing Date Title PO8003 Jul. 15, 1997Supply Method and Apparatus (F1) PO8005 Jul. 15, 1997 Supply Method andApparatus (F2) PO9404 Sep. 23, 1997 A Device and Method (F3)MEMS Technology

Further, the present application may utilize advanced semiconductormicroelectromechanical techniques in the construction of large arrays ofink jet printers. Suitable microelectromechanical techniques aredescribed in the following Australian provisional patent specificationsincorporated here by cross-reference:

Australian Provisional Number Filing Date Title PO7943 Jul. 15, 1997 Adevice (MEMS01) PO8006 Jul. 15, 1997 A device (MEMS02) PO8007 Jul. 15,1997 A device (MEMS03) PO8008 Jul. 15, 1997 A device (MEMS04) PO8010Jul. 15, 1997 A device (MEMS05) PO8011 Jul. 15, 1997 A device (MEMS06)PO7947 Jul. 15, 1997 A device (MEMS07) PO7945 Jul. 15, 1997 A device(MEMS08) PO7944 Jul. 15, 1997 A device (MEMS09) PO7946 Jul. 15, 1997 Adevice (MEMS10) PO9393 Sep. 23, 1997 A Device and Method (MEMS11) PP0875Dec. 22, 1997 A device (MEMS12) PP0894 Dec. 22, 1997 A Device and Method(MEMS13)IR Technologies

Further, the present application may include the utilization of adisposable camera system such as those described in the followingAustralian provisional patent specifications incorporated here bycross-reference:

Australian Provisional Number Filing Date Title PP0895 Dec. 12, 1997 AnImage Creation Method and Apparatus (IR01) PP0870 Dec. 12, 1997 A Deviceand Method (IR02) PP0869 Dec. 12, 1997 A Device and Method (IR04) PP0887Dec. 12, 1997 Image Creation Method and Apparatus (IR05) PP0885 Dec. 12,1997 An Image Production System (IR06) PP0884 Dec. 12, 1997 ImageCreation Method and Apparatus (IR10) PP0886 Dec. 12, 1997 Image CreationMethod and Apparatus (IR12) PP0871 Dec. 12, 1997 A Device and Method(IR13) PP0876 Dec. 12, 1997 An Image Processing Method and Apparatus(IR14) PP0877 Dec. 12, 1997 A Device and Method (IR16) PP0878 Dec. 12,1997 A Device and Method (IR17) PP0879 Dec. 12, 1997 A Device and Method(IR18) PP0883 Dec. 12, 1997 A Device and Method (IR19) PP0880 Dec. 12,1997 A Device and Method (IR20) PP0881 Dec. 12, 1997 A Device and Method(IR21)DotCard Technologies

Further, the present application may include the utilization of a datadistribution system such as that described in the following Australianprovisional patent specifications incorporated here by cross-reference:

Australian Provisional Number Filing Date Title PP2370 Mar. 16, 1998Data Processing Method and Apparatus (Dot01) PP2371 Mar. 16, 1998 DataProcessing Method and Apparatus (Dot02)Artcam Technologies

Further, the present application may include the utilization of cameraand data processing techniques such as an Artcam type device asdescribed in the following Australian provisional patent specificationsincorporated here by cross-reference:

Australian Provisional Number Filing Date Title PO7991 Jul. 15, 1997Image Processing Method and Apparatus (ART01) PO8505 11 Aug. 1997 ImageProcessing Method and Apparatus (ART01a) PO7988 Jul. 15, 1997 ImageProcessing Method and Apparatus (ART02) PO7993 Jul. 15, 1997 ImageProcessing Method and Apparatus (ART03) PO8012 Jul. 15, 1997 ImageProcessing Method and Apparatus (ART05) PO8017 Jul. 15, 1997 ImageProcessing Method and Apparatus (ART06) PO8014 Jul. 15, 1997 MediaDevice (ART07) PO8025 Jul. 15, 1997 Image Processing Method andApparatus (ART08) PO8032 Jul. 15, 1997 Image Processing Method andApparatus (ART09) PO7999 Jul. 15, 1997 Image Processing Method andApparatus (ART10) PO7998 Jul. 15, 1997 Image Processing Method andApparatus (ART11) PO8031 Jul. 15, 1997 Image Processing Method andApparatus (ART12) PO8030 Jul. 15, 1997 Media Device (ART13) PO8498 Aug.11, 1997 Image Processing Method and Apparatus (ART14) PO7997 Jul. 15,1997 Media Device (ART15) PO7979 Jul. 15, 1997 Media Device (ART16)PO8015 Jul. 15, 1997 Media Device (ART17) PO7978 Jul. 15, 1997 MediaDevice (ART18) PO7982 Jul. 15, 1997 Data Processing Method and Apparatus(ART19) PO7989 Jul. 15, 1997 Data Processing Method and Apparatus(ART20) PO8019 Jul. 15, 1997 Media Processing Method and Apparatus(ART21) PO7980 Jul. 15, 1997 Image Processing Method and Apparatus(ART22) PO7942 Jul. 15, 1997 Image Processing Method and Apparatus(ART23) PO8018 Jul. 15, 1997 Image Processing Method and Apparatus(ART24) PO7938 Jul. 15, 1997 Image Processing Method and Apparatus(ART25) PO8016 Jul. 15, 1997 Image Processing Method and Apparatus(ART26) PO8024 Jul. 15, 1997 Image Processing Method and Apparatus(ART27) PO7940 Jul. 15, 1997 Data Processing Method and Apparatus(ART28) PO7939 Jul. 15, 1997 Data Processing Method and Apparatus(ART29) PO8501 Aug. 11, 1997 Image Processing Method and Apparatus(ART30) PO8500 Aug. 11, 1997 Image Processing Method and Apparatus(ART31) PO7987 Jul. 15, 1997 Data Processing Method and Apparatus(ART32) PO8022 Jul. 15, 1997 Image Processing Method and Apparatus(ART33) PO8497 Aug. 11, 1997 Image Processing Method and Apparatus(ART30) PO8029 Jul. 15, 1997 Sensor Creation Method and Apparatus(ART36) PO7985 Jul. 15, 1997 Data Processing Method and Apparatus(ART37) PO8020 Jul. 15, 1997 Data Processing Method and Apparatus(ART38) PO8023 Jul. 15, 1997 Data Processing Method and Apparatus(ART39) PO9395 Sep. 23, 1997 Data Processing Method and Apparatus (ART4)PO8021 Jul. 15, 1997 Data Processing Method and Apparatus (ART40) PO8504Aug. 11, 1997 Image Processing Method and Apparatus (ART42) PO8000 Jul.15, 1997 Data Processing Method and Apparatus (ART43) PO7977 Jul. 15,1997 Data Processing Method and Apparatus (ART44) PO7934 Jul. 15, 1997Data Processing Method and Apparatus (ART45) PO7990 Jul. 15, 1997 DataProcessing Method and Apparatus (ART46) PO8499 Aug. 11, 1997 ImageProcessing Method and Apparatus (ART47) PO8502 Aug. 11, 1997 ImageProcessing Method and Apparatus (ART48) PO7981 Jul. 15, 1997 DataProcessing Method and Apparatus (ART50) PO7986 Jul. 15, 1997 DataProcessing Method and Apparatus (ART51) PO7983 Jul. 15, 1997 DataProcessing Method and Apparatus (ART52) PO8026 Jul. 15, 1997 ImageProcessing Method and Apparatus (ART53) PO8027 Jul. 15, 1997 ImageProcessing Method and Apparatus (ART54) PO8028 Jul. 15, 1997 ImageProcessing Method and Apparatus (ART56) PO9394 Sep. 23, 1997 ImageProcessing Method and Apparatus (ART57) PO9396 Sep. 23, 1997 DataProcessing Method and Apparatus (ART58) PO9397 Sep. 23, 1997 DataProcessing Method and Apparatus (ART59) PO9398 Sep. 23, 1997 DataProcessing Method and Apparatus (ART60) PO9399 Sep. 23, 1997 DataProcessing Method and Apparatus (ART61) PO9400 Sep. 23, 1997 DataProcessing Method and Apparatus (ART62) PO9401 Sep. 23, 1997 DataProcessing Method and Apparatus (ART63) PO9402 Sep. 23, 1997 DataProcessing Method and Apparatus (ART64) PO9403 Sep. 23, 1997 DataProcessing Method and Apparatus (ART65) PO9405 Sep. 23, 1997 DataProcessing Method and Apparatus (ART66) PP0959 Dec. 16, 1997 A DataProcessing Method and Apparatus (ART68) PP1397 Jan. 19, 1998 A MediaDevice (ART69)

1. A recyclable, one-time use, print on demand, digital cameracomprising: an image sensor device for sensing an image; a processingmeans for processing said sensed image; a pagewidth print head forprinting said sensed image; an ink supply means for supplying ink to theprint head; a supply of print media in the form of a roll on to whichsaid image is printed, the supply of print media being pre-marked withtokens designating that postage has been paid so that each image printedout on the print media has one such token associated with the image; anda platen unit for guiding the print media past the pagewidth print head,the platen unit including a cutting mechanism that traverses the platenunit and a capping mechanism operated by action of a solenoid coil forrecapping the pagewidth print head when not in use.
 2. The camera ofclaim 1 in which the supply of print media is in the form of a roll, thetokens being pre-printed at regularly spaced intervals on one surface ofthe print media.
 3. The camera of claim 2 in which each token has anaddress zone and a blank zone for writing associated with it on said onesurface to provide a postcard effect.
 4. The camera of claim 2 in whicheach image is printed on an opposed surface of the print media.
 5. Thecamera of claim 1 in which the token is in a currency of a country inwhich the camera is bought, with a notice to that effect being carriedon an exterior of the camera.